Electrolyte Exchange Research Articles

Transcriptome Profiling of Gill Tissue in Regionally Bred and Globally Farmed Rainbow Trout Strains Reveals Different Strategies for Coping with Thermal Stress

Thermal stress can pose a major challenge to salmonid fish. A 4x44K oligonucleotide microarray approach was used to screen for genetically determined variations of a temperature stress response during acclimation in fish gills, a highly specialized and complex organ responsible for gas and electrolyte exchange as well as excretion. The comparison addressed transcriptional changes in the local breeding strain BORN and imported (TCO) rainbow trout after graded 2-week acclimation to 8 and 23°C. Besides well-characterized mediators of thermoregulation such as genes encoding cold-inducible RNA-binding protein and heat shock proteins, the present microarray study suggests several new candidate genes commonly regulated in gills of the two trout lines. Having identified the differential expression of thermoregulated genes as duplicated paralogues, they were subsequently validated in a gill cell model. Moreover, the comparison of transcriptome profiles provides evidence for distinctively employed expression patterns. The induction of genes encoding factors of the early innate immunity in BORN trout upon warming contrasts with the increased expression of adaptive immune genes in import trout. Cold acclimation induced genes assigned to the functional categories "cell death" and "ion channel activity" in import trout, but repressed "lipid metabolism." This manuscript provides an overview of the genes of the multifunctional gills in rainbow trout that are mandated after temperature change, suggesting links between the different temperature-dependent pathways and gene networks.

Role of the Cathode Microporous Layer in a PEMFC

The role of the cathode microporous layer (MPL) of the gas diffusion layer in a polymer electrolyte exchange membrane fuel cell was investigated by comparing the performance of several cells containing different MPLs. MPLs were prepared with different hydrophobic agent contents to impart different water capillary pressures and hydrophobic properties. Experimental data were evaluated according to the water vapor activity of the cathode, which was modified with the capillary pressure of the MPL. As a result, the modified activity was determined to be a key factor to explain the occurrence of cathode flooding. Liquid water saturation in the diffusion media and the cathode catalyst layer (CCL) are determined by the balance of capillary pressures of the pores of each layer. Increase of the diffusion resistance of oxygen in the CCL is significant, while that in the diffusion media is moderate, which indicates that the CCL is susceptible to flooding.

Tailoring nanostructured catalysts for electrochemical energy conversion systems

AbstractThis review covers topics related to the synthesis of nanoparticles, the anodic and cathodic electrochemical reactions and low temperature electrochemical energy devices. The thermodynamic aspects of nucleation and growth of nanoparticles are discussed. Different methods of chemical synthesis such as w/o microemulsion, Bönnemann, polyol and carbonyl are presented. How the electrochemical reactions take place on the surface of the catalytic nanoparticles and the importance of the substrate is put in evidence. The use of nanomaterials in low temperature energy devices such as H2/O2 polymer electrolyte or proton exchange membrane fuel cell (PEMFC) and micro-direct methanol fuel cell (μDMFC), as well as recent progress and durability, is discussed. Special attention is given to the novel laminar flow fuel cell (LFFC). This review starts with the genesis of catalytic nanoparticles, continues with the surface electrochemical reactions that occur on them, and finally it discusses their application in electrochemical energy devices such as low temperature fuel cells or Li-air batteries.

1022 Immunoregulatory Mechanisms of Childs Food in the Children with Dispepsia Syndrom

BackgroundWe studied the influence of child’s food on the state of homoeostasis in the children and developed recommendations by correction of dyspepsia syndrome.MaterialsWere observed 27 children with dispepsia syndrom in...

A quantitative analysis of electrolyte exchange in the salivary duct

A healthy salivary gland secretes saliva in two stages. First, acinar cells generate primary saliva, a plasma-like, isotonic fluid high in Na(+) and Cl(-). In the second stage, the ducts exchange Na(+) and Cl(-) for K(+) and HCO(3)(-), producing a hypotonic final saliva with no apparent loss in volume. We have developed a tool that aims to understand how the ducts achieve this electrolyte exchange while maintaining the same volume. This tool is part of a larger multiscale model of the salivary gland and can be used at the duct or gland level to investigate the effects of genetic and chemical alterations. In this study, we construct a radially symmetric mathematical model of the mouse salivary gland duct, representing the lumen, the cell, and the interstitium. For a given flow and primary saliva composition, we predict the potential differences and the luminal and cytosolic concentrations along a duct. Our model accounts well for experimental data obtained in wild-type animals as well as knockouts and chemical inhibitors. Additionally, the luminal membrane potential of the duct cells is predicted to be very depolarized compared with acinar cells. We investigate the effects of an electrogenic vs. electroneutral anion exchanger in the luminal membrane on concentration and the potential difference across the luminal membrane as well as how impairing the cystic fibrosis transmembrane conductance regulator channel affects other ion transporting mechanisms. Our model suggests the electrogenicity of the anion exchanger has little effect in the submandibular duct.

Препарат високої метаболічної активності кокарніт у лікуванні діабетичної автономної нейропатії серця

Left ventricular diastolic dysfunction in patients with diabetes is formed in the absence of atherosclerotic changes as a consequence of diabetic cardiac autonomic neuropathy in the early stages of diabetes. Progression of autonomic cardiac neuropathy in cardio-vascular type is associated with the violation of energy supply of cells, protein synthesis, electrolyte exchange, the exchange of trace elements, oxidation reduction processes, oxygen-transport function of blood, so that metabolic therapy is carried out to optimize the processes of formation and energy costs. The drug cocarnit activates processes of aerobic oxidation of glucose, as well as providing regulatory influence on the oxidation of fatty acids. Applying of cocarnit in complex therapy in patients with diabetic cardiac autonomic neuropathy found improvement of left ventricular diastolic function, and positive dynamics in the efferent activity balance of the sympathetic and parasympathetic control of heart rate variability, which provides the regression of clinical symptoms.

Chaotic behavior of ion exchange phenomena in polymer gel electrolytes through irradiated polymeric membrane

A desktop experiment has been done to show the nonlinearity in the I–V characteristics of an ion conducting electrochemical micro-system. Its chaotic dynamics is being reported for the first time which has been captured by an electronic circuit. Polyvinylidene fluoride-co-hexafluoropropene (PVdF-HFP) gel electrolyte comprising of a combination of plasticizers (ethylene carbonate and propylene carbonate) and salts have been prepared to study the exchange of ions through porous polyethylene terephthalate (PET) membranes. The nonlinearity of this system is due to the ion exchange of the polymer gel electrolytes (PGEs) through a porous membrane. The different regimes of spiking and non-spiking chaotic motions are being presented. The possible applications are highlighted.

Clinical experience with Uralyt-U used in patients with gout and nephrolithiasis

The impact of a 4-week course of therapy with Uralyt-U (potassium-sodium hydrocitrate) on uric acid (UA) metabolic parameters was studied in patients with gout and nephrolithiasis. Elevated daily urinary excretion of UA was found to be directly correlated with its lower serum level after 4-week therapy with Uralyt-U (p < 0.05), resulting in improvement and normalization of UA metabolism. Uralyt-U therapy is safe and causes no worsening of the parameters of hepatic and renal function and electrolyte exchange.

Pressure and temperature transients of a cryogenic distillation system during abnormal operation or accidents

Cryogenic distillation system (CDS) is being employed, among other applications, in tritium separation technologies. CDS in combination with a Liquid Phase Catalytic Exchange (LPCE) process or with a Combined Electrolytic Catalytic Exchange (CECE) process is used for tritium removal/recovery from tritiated water. Large amounts of tritiated water can be produced during long time operation of CANDU reactors or in case of ITER mainly by the Detritiation System (DS). The CDS used to remove/recover tritium consists of a cascade of cryogenic distillation columns and a refrigeration unit which provides the cooling capacity for the condensers of CD columns. The columns, together with the condensers and the process heat-exchangers are accommodated in a vacuum insulated cold box. During abnormal events or accidents, significant amount of liquid hydrogen–deuterium–tritium or helium refrigerant can be spilt inside the cold box or even into the building. The paper analyzes some critical scenarios due to single failure mode or various combinations of failures such as: loss of refrigerant in the columns; loss of vacuum insulation; process liquid spilt into the cold box; refrigerant fails into cryogenic distillation columns.

Development of an Automated Diffusion Scrubber-Conductometry System for Measuring Atmospheric Ammonia

A semi-continuous and automated method for quantifying atmospheric ammonia at the parts per billion level has been developed. The instrument consists of a high efficiency diffusion scrubber, an electrolytic on-line anion exchange device, and a conductivity detector. Water soluble gases in sampled air diffuse through the porous membrane and are absorbed in an absorbing solution. Interferences are eliminated by using an anion exchange devises. The electrical conductivity of the solution is measured without chromatographic separation. The collection efficiency was over 99%. Over the 0-200 ppbv concentration range, the calibration was linear with = 0.99. The lower limit of detection was 0.09 ppbv. A parallel analysis of Seoul air over several days using this method and a diffusion scrubber coupled to an ion chromatography system showed acceptable agreement, = 0.940 (n = 686). This method can be applied for ambient air monitoring of ammonia.

Molecular biology of the blood-brain and the blood-cerebrospinal fluid barriers: similarities and differences

Efficient processing of information by the central nervous system (CNS) represents an important evolutionary advantage. Thus, homeostatic mechanisms have developed that provide appropriate circumstances for neuronal signaling, including a highly controlled and stable microenvironment. To provide such a milieu for neurons, extracellular fluids of the CNS are separated from the changeable environment of blood at three major interfaces: at the brain capillaries by the blood-brain barrier (BBB), which is localized at the level of the endothelial cells and separates brain interstitial fluid (ISF) from blood; at the epithelial layer of four choroid plexuses, the blood-cerebrospinal fluid (CSF) barrier (BCSFB), which separates CSF from the CP ISF, and at the arachnoid barrier. The two barriers that represent the largest interface between blood and brain extracellular fluids, the BBB and the BCSFB, prevent the free paracellular diffusion of polar molecules by complex morphological features, including tight junctions (TJs) that interconnect the endothelial and epithelial cells, respectively. The first part of this review focuses on the molecular biology of TJs and adherens junctions in the brain capillary endothelial cells and in the CP epithelial cells. However, normal function of the CNS depends on a constant supply of essential molecules, like glucose and amino acids from the blood, exchange of electrolytes between brain extracellular fluids and blood, as well as on efficient removal of metabolic waste products and excess neurotransmitters from the brain ISF. Therefore, a number of specific transport proteins are expressed in brain capillary endothelial cells and CP epithelial cells that provide transport of nutrients and ions into the CNS and removal of waste products and ions from the CSF. The second part of this review concentrates on the molecular biology of various solute carrier (SLC) transport proteins at those two barriers and underlines differences in their expression between the two barriers. Also, many blood-borne molecules and xenobiotics can diffuse into brain ISF and then into neuronal membranes due to their physicochemical properties. Entry of these compounds could be detrimental for neural transmission and signalling. Thus, BBB and BCSFB express transport proteins that actively restrict entry of lipophilic and amphipathic substances from blood and/or remove those molecules from the brain extracellular fluids. The third part of this review concentrates on the molecular biology of ATP-binding cassette (ABC)-transporters and those SLC transporters that are involved in efflux transport of xenobiotics, their expression at the BBB and BCSFB and differences in expression in the two major blood-brain interfaces. In addition, transport and diffusion of ions by the BBB and CP epithelium are involved in the formation of fluid, the ISF and CSF, respectively, so the last part of this review discusses molecular biology of ion transporters/exchangers and ion channels in the brain endothelial and CP epithelial cells.

Ethanol, Acetaldehyde and Acetic Acid Adsorption/Electrooxidation on a Pt Thin Film Electrode under Continuous Electrolyte Flow: An in Situ ATR-FTIRS Flow Cell Study

The interaction of ethanol and its oxidative C2 derivatives acetaldehyde and acetic acid with a Pt thin film electrode in 0.5 M H2SO4 solution was investigated by in situ Fourier transform infrared spectroscopy in an attenuated total reflection configuration (ATR-FTIRS). Time-resolved spectro-electrochemical measurements were carried out under well-defined mass transport to/from the electrode in a thin-layer flow cell setup, allowing to in situ monitor the electrode∣electrolyte interface and the formation/removal of adsorbed species in both potentiodynamic and potentiostatic mode. Spectro-electrochemical transients at constant electrode potentials upon electrolyte exchange were employed to identify adsorbed species and their temporal evolution, followed by subsequent stripping of the resulting adsorbates in the supporting electrolyte. Adsorption transient and stripping measurements performed at different constant potentials lead to the following conclusions. (i) Ethanol does not adsorb on Pt at potential ...

Principes et modalités d’application de l’hémodialyse au traitement de l’insuffisance rénale chronique

"Hemodialysis" is the generic term that refers to all forms of renal replacement therapy (RRT) able to restore periodically the "internal milieu" composition in end stage renal disease patients (ESRD). RRT includes several modalities (hemodialysis, hemofiltration, hemodiafiltration) that induce basic physical principles (diffusion, convection, adsorption) via an exchange module (dialyser) and an electrolytic exchange solution (dialysis fluid). The cleansing property of the RRT depends on different factors: the treatment modality itself, the uremic toxin considered, patient's characteristic and the operational conditions (duration of treatment, session frequency, blood and dialysate flow rates). Solute instantaneous clearances reflect the dialyser's performances used in optimal conditions but not necessarily the body clearance. The effective solute body clearance is more difficult to assess in clinical practice since it includes some variables such as the treatment duration, the biological complexity of internal milieu and the variability of the patient/dialysis system interaction. The "dialysis adequacy" concept that governs the treatment efficacy in ESRD patients could not be reduced to the urea Kt/V ratio. It must integrate a selection of pertinent clinical and biological markers covering the complete spectrum of uremic abnormalities. Adequate knowledge of those basic physical principles that control the solute exchange in hemodialysis patient is highly recommended to any nephrologist who looks forward to improve treatment efficacy and reduce mortality in ESRD patients.

Design and experimental activities in view of Water Detritiation–Isotopic Separation Systems combination in TRENTA facility

To support the research activities needed to characterize the performance of various components for the Water Detritiation System (WDS) and the Isotope Separation System (ISS) processes needed for the ITER design, an experimental facility called TRENTA, simulating for the ITER WDS and ISS protium separation column, has been commissioned at Tritium Laboratory Karlsruhe (TLK). The TRENTA facility has been conceived to allow operation in a closed loop with respect to tritium inventory and to allow investigations of key design and operation issues of combined CECE (Combined Electrolytic Catalytic Exchange) and CD (Cryogenic Distillation) processes in similar conditions as envisaged for the ITER WDS–ISS. Activities combining CECE and CD processes are on going at TLK. For the CD system, dedicated heat-exchangers have been designed and manufactured to make the combination possible. The system of heat-exchangers has to provide a double barrier to avoid tritium contamination of the helium stream. The design of the heat-exchangers for feeding of the CD column, equilibrator loop and condenser will be presented. In addition, the ongoing experimental activities for to the investigation of different CD fillings will be presented.

Generation of a conditional null allele for Cftr in mice

The cystic fibrosis transmembrane conductance regulator (CFTR) gene encodes a cAMP-regulated chloride channel that is important in controlling the exchange of fluid and electrolytes across epithelial cells. Mutation of CFTR can lead to cystic fibrosis (CF), the most common lethal genetic disease in Caucasians. CF is a systemic illness with multiple organ systems affected including pulmonary, gastrointestinal, pancreatic, immune, endocrine, and reproductive systems. To understand the role of CFTR in the various tissues in which it is expressed, we generated a murine conditional null allele of Cftr (Cftr(fl10)) in which loxP sites were inserted around exon 10 of the Cftr gene. The Cftr(fl10) allele was validated by generating constitutive Cftr null (Cftr(Delta10)) mice using the protamine-cre system. The Cftr(Delta10/Delta10) mice displayed almost identical phenotypes to previously published CF mouse models, including poor growth, decreased survival, intestinal obstruction, and loss of Cftr function as assessed by electrophysiology measurements on gut and nasal epithelium. Mice containing the conditional null Cftr allele will be useful in future studies to understand the role of Cftr in specific tissues and developmental time points and lead to a better understanding of CF disease.

Effect of anionic and cationic exchange polymeric layers on current–voltage curves and chronopotentiometry of a charged composite membrane

In this paper, the effect of an anionic (polyvinyl pyridine iodide, AM-1) and cationic (polystyrene sulfonate sodium, CM-1) exchange polymer layer on the chronopotentiometry (CP) and current voltage curves ( I–V) of a charged composite membrane are investigated. Also, the ion transport near the interface between electrolyte and ionic exchange polymer membranes (anionic and cationic ones) and a charged mosaic polymer composite membrane is studied. The results show that both anionic and cationic polymer exchange membranes exhibit a lower voltage drop over the range of applied current density and possess favorable industrial application potentials, especially at a low KCl concentration. While the charged mosaic polymer composite membrane did not show any current–voltage change, irrespective of the type and the concentration of used electrolyte. CP and I–V measurements are effectively used to give some fundamental understanding for ion transport behavior of an ion exchange polymer membrane near the interface.

An efficient elution method of tetravalent uranium from anion exchanger by using formic acid solution

In recent years, we have been investigating the development of the ERIX (The Electrolytic Reduction and Ion Exchange) process for reprocessing spent FBR-MOX fuel. This process uses electrolytic reduction and ion exchange techniques to recover U, Pu from spent FBR-MOX fuel solution. It was found that despite of the high nitric acid concentration, U(VI) can be effectively reduced to U(IV) using a flow type electrolytic cell in the existence of hydrazine and the U(IV) can be completely separated from fission products by the anion exchanger, AR-01. In addition, it was proposed that a part of U is assigned to be recovered together with Pu and Np for reusing as a FBR-MOX fuel. For that purpose, we are investigating an efficient elution method of Pu(IV) and U(IV) from AR-01. In this work, to develop an efficient elution method of U(IV) from AR-01, we have examined the U(IV) elution behavior by formic acid and the complex-formation of U(IV) with HCOO−.

Effect of dronedarone on renal function in healthy subjects

To assess the effects of dronedarone on renal function and tubular cation handling. Twelve healthy males were enrolled in a randomized, cross-over, placebo-controlled, double-blind study. They received 400 mg dronedarone or placebo twice daily for 7 days. Baseline and on-treatment renal function tests were performed under strict standardization of intakes, by assessing creatinine, sinistrin, para-amino-hippurate (PAH) and N-methylnicotinamide (NMN) CLs, and electrolyte excretion. Compared with placebo, dronedarone significantly decreased renal creatinine CL (mean 138-119 ml min(-1) after dronedarone vs. 142-149 ml min(-1) after placebo) and NMN CL (448-368 ml min(-1)vs. 435-430 ml min(-1)), but did not alter renal sinistrin CL, PAH CL and other renal parameters. Dronedarone reduces renal creatinine and NMN clearance by about 18%, without evidence of an effect on GFR, renal plasma flow or electrolyte exchanges. This suggests a specific partial inhibition of tubular organic cation transporters (OCT). A limited increase in serum creatinine is therefore expected with dronedarone treatment, but does not mean there is a decline in renal function.

Reduction of U(VI) and some fission products in HNO3 media by galvanostatic electrolysis

Abstract In order to investigate the applicability of the galvanostatic reduction of uranium(VI) to U(IV) in the electrolytic reduction and ion exchange (ERIX) Process, a novel aqueous reprocessing technique for spent mixed uranium and plutonium oxide (MOX) fuels for fast-breeder reactors (FBR), an improved electrolytic cell was developed and fundamental electrolytic properties were examined using U and some fission products (FPs) in HNO3 media. As the result of the electrolysis for a 200 cm3 solution of 0.5 M (M = mol/dm3) U(VI), 6 M HNO3, and 0.5 M N2H4, it was found that more than 99% of U(VI) was reduced to U(IV) before the shift to the side reaction when the initial constant current supplied was no higher than 10 A. It was also found that the reduction of U(VI) to U(IV) was achieved using the cell under coexistence with the FPs, e.g. noble metals, which are easily deposited by the electrolytic reduction.

Copper sulfide nanostripe patterns at the Au(111)/electrolyte interface studied by in situ STM

One monolayer of Cu was prepared on Au(111) by underpotential deposition from CuSO4/H2SO4 solution and, by two electrolyte exchanges for (i) Cu-free H2SO4 and (ii) NaOH/Na2S solution, exposed to bisulfide. This procedure leads to several incommensurate phases with characteristic stripe patterns. These are irreversibly displaced upon cathodic potential sweeps by different structures, which, after returning to the initial potential, transform into the rectangular CuxS phase already known for the sulfidation of a Cu submonolayer on Au(111).