Chloride Absorption Research Articles

The effect of temperature on the exciton absorption of copper chloride and copper bromide nanocrystals in potassium-aluminum-borate glass

The absorption spectra of nanosized crystals of copper (I) halides distributed in the potassium-aluminum borate glass system were investigated in the region of the exciton absorption band in the temperature range from 20 to 300°C. The temperature dependences of the exciton absorption band of CuHal (Hal = Cl, Br) nanocrystals, which were obtained upon the heating and cooling of the sample, have a form of hysteresis. The melting (140–240°C) and crystallization (35–105°C) temperatures of copper (I) halide nanocrystals contained in the potassium-aluminum borate glass were determined by the optical spectroscopy method.

SALT STRESS TOLERANCE IN ACIDIC AND SWEET MANDARINS

Mandarin genotypes can be split in two main groups: the acidic and the sweet mandarins. Commonly, acidic are used as rootstocks when sweet mandarins are the varieties that are consumed as fruits. The acidic 'Cleopatra' mandarin (Citrus reshni Hort. ex Tan.) is considered to be the most salt stress tolerant rootstock since it is able to limit the absorption of chloride and sodium at root level. As a consequence, limited amount of toxic ions are translocated from root to leaves. If salt stress tolerance of 'Cleopatra' mandarin and its hybrids has been well documented, little data exist for sweet mandarins. We investigated 16 genotypes representing a large diversity in mandarins subjected to salt stress. Physiological parameters such as stomatal conductance and leaf chloride contents were analyzed. If most of the acidic varieties were tolerant, also some sweet varieties presented traits of tolerance. Taking into account the results of leaf ion contents, we observed that large leaf chloride contents were not always associated with sensitivity. (Resume d'auteur)

Complicaciones metabólicas y óseas de las derivaciones urinarias

Hyperchloremic metabolic acidosis is a complication of urinary diversion using ileum or colon. Its prevalence ranges from 25% and 46% depending on the procedure used and renal function of the patient. It is a consequence of intestinal fluid and electrolyte exchange between intestinal mucosa and urine. The main mechanism is absorption of ammonium and chloride from urine. Long-term chronic metabolic acidosis in these patients may lead to impaired bone metabolism and osteomalacia. Regular monitoring of pH, chlorine, bicarbonate, and calcium-phosphorus metabolism is therefore essential for early diagnosis and treatment.

Unusual Case of Celiac Disease

Introduction: Celiac crisis is an uncommon presentation in adults. While serology is sensitive and specific, it can be negative in some patients, which make intestinal biopsy indispensable in diagnosis. An 80-year-old woman presented to the hospital with loose stools; 15 episodes /day for 1 week, and increasing weakness. She had 10-year history of 3-4 loose stools/day. She has no significant past medical or family history, nor recent travel history. Labs showed low sodium, potassium, chloride, metabolic acidosis, and acute renal failure. She was initially treated with intravenous normal saline and bicarbonate; however, diarrhea continued. Investigations showed elevated stool osmotic gap and negative stool cultures for bacteria, ova, and parasites. Anti-endomysial (EMA) and anti-tissue transglutaminase (TTG) antibodies and 5HIAA were normal. Colonoscopy demonstrated normal colonic mucosa; however, random biopsies demonstrated lymphocytic colitis and increased intraepithelial lymphocytes. Small bowel biopsy showed partial villous atrophy, crypt hyperplasia, and increased inflammatory infiltrate consistent with celiac disease. She was started on a gluten-free diet, and over the subsequent weeks, she had resolution of symptoms. Two interesting aspects of this case are that she presented with celiac crisis, which is rare in adults, and diagnosis depended solely on biopsy because she did not have antibodies to EMA and TTG. Celiac crisis is a life-threatening syndrome of unclear etiology. Manifestations include diarrhea and electrolyte disturbances. It was thought to occur exclusively in patients younger than 2 years of age. The association between microscopic colitis and celiac disease may be 1 factor that contributes to the development celiac crisis due to defective active and passive absorption of sodium and chloride, and reduced chloride-bicarbonate exchange. Diagnosis of celiac disease is based on serologic tests of specific antibodies, including EMA and TTG antibodies, which are highly specific and sensitive (95% and 96%). It was found that 7% of patients were negative for both auto-antibodies despite having normal IgA levels. Intestinal biopsy is the gold standard for diagnosis because EMA and TTG antibodies decrease in patients with partial villous atrophy. Histological criteria are increased intraepithelial lymphocyte infiltrate, crypt hyperplasia, and villous atrophy. Gluten-free diet is the mainstay of treatment with dramatic response and improvement in symptoms. Although celiac crisis is an uncommon presentation in adults, it should be considered in patients presenting with unexplained severe diarrhea and metabolic acidosis, even if EMA and TTG antibodies are negative.

Application of Two Different Methods for Determination of Water and Chloride Transport Parameters of Building Stones

The transport of 1M NaCl water solution in three different types of sandstones is studied For basic characterization of studied materials, their chemical composition, porosity, bulk density and matrix density are accessed. The chloride transport is analyzed using two different methods. In the first one, the chloride absorption coefficient is measured on the basis of a modified sorptivity concept. The second method consists in carrying out an inverse analysis of experimentally measured moisture and chloride concentration profiles, leading to the determination of chloride diffusion coefficient as a function of chloride concentration, and moisture diffusivity as a function of moisture content. The chloride transport properties obtained for the particular studied materials are compared and the observed differences are discussed.

Mathematical modeling of chemisorption process at chlororganic productions

The data on mathematical modeling of simultaneous chlorine and hydrogen chloride absorption by alkaline solutions are given in the paper. The purpose of the paper is to analyze the sanitary column operation and develop the mathematical model of exhaust gas purification from chlorine and hydrogen chloride. The exhaust gas neutralization process proceeds in countercurrent absorption columns, which are irrigated by the alkaline solution. Mathematical model of the process includes a system of differential equations of component-wise material balance. The material balance equation system describes the change in the component concentration according to the column height. The equation system is written taking into account the assumptions that the process is isothermal, proceeds in the full displacement in both phases; only hydrogen chloride and chlorine are absorbed from the gas flow and chemisorption reaction in the liquid phase runs immediately. The reaction surface in this case coincides with the interface, the reaction proceeds in the external diffusion region. The process rate is determined only by the diffusion rate of the components from the gas flow to the reaction surface. The actual kinetics is not taken into account. The equations of the mathematical model allow to calculate the concentration profiles of the components according to the column height. Using the mathematical model of chemisorption of two gases allows to make calculations of similar columns at the design stage and the stage of production process investigation.

Chlorine and hydrogen chloride gas emissions cleaning in vinylchloride production

The paper gives the data on mathematical modeling of simultaneous absorption of chlorine and hydrogen chloride by alkaline solutions. The mathematical model of the process includes the system of differential equations of component-wise material balance and the system of kinetic equations. The system of material balance equations describes the change in concentrations of components along the column height. For its solving it is necessary to know the numerical values of chemisorption acceleration coefficients. They are determined from the system of equations describing the inetics of chemisorption. The gradients of components oncentrations create various conditions of mass transfer processes along the height of the column. This leads to the fact that in one unit there can be various zones of hemisorption process along the height of the packed layer. Each zone is characterized by its reaction order for absorbing component and its kinetic constants. Various zones of the course of binary absorption with chemical reaction were considered. Taking into account the zones, the mathematical model of chemisorption was designed for the countercurrent packed absorber. The peculiarity of the developed mathematical model is the lack of iterative algorithm for calculation. The use of band mathematical model of chemisorption of two gases allows calculation of similar columns at the stages of design and research of industrial processes. The results can be used for calculation and optimization of existing columns of gas emission neutralization in organochlorine production.

Absorption of HCl by calcium-based sorbents during filtration combustion in a continuous reactor

Experimental data on hydrogen chloride absorption by calcium-containing sorbents in solid fuel gasification in a continuous filtration combustion reactor are presented. The addition of the sorbents to the stock allows up to 80% of the chlorine to be sorbed. The chlorine remains as calcium chloride in the solid combustion residue. The incompleteness of HCl sorption is due to the hydrolysis of the resulting calcium chloride in the high-temperature zone of combustion.

Overexpression of Pendrin in Intercalated Cells Produces Chloride-Sensitive Hypertension

Inherited and acquired disorders that enhance the activity of transporters mediating renal tubular Na(+) reabsorption are well established causes of hypertension. It is unclear, however, whether primary activation of an Na(+)-independent chloride transporter in the kidney can also play a pathogenic role in this disease. Here, mice overexpressing the chloride transporter pendrin in intercalated cells of the distal nephron (Tg(B1-hPDS) mice) displayed increased renal absorption of chloride. Compared with normal mice, these transgenic mice exhibited a delayed increase in urinary NaCl and ultimately, developed hypertension when exposed to a high-salt diet. Administering the same sodium intake as NaHCO3 instead of NaCl did not significantly alter BP, indicating that the hypertension in the transgenic mice was chloride-sensitive. Moreover, excessive chloride absorption by pendrin drove parallel absorption of sodium through the epithelial sodium channel ENaC and the sodium-driven chloride/bicarbonate exchanger (Ndcbe), despite an appropriate downregulation of these sodium transporters in response to the expanded vascular volume and hypertension. In summary, chloride transport in the distal nephron can play a primary role in driving NaCl transport in this part of the kidney, and a primary abnormality in renal chloride transport can provoke arterial hypertension. Thus, we conclude that the chloride/bicarbonate exchanger pendrin plays a major role in controlling net NaCl absorption, thereby influencing BP under conditions of high salt intake.

Sulfate secretion and chloride absorption are mediated by the anion exchanger DRA (Slc26a3) in the mouse cecum

Inorganic sulfate (SO₄²⁻) is essential for a multitude of physiological processes. The specific molecular pathway has been identified for uptake from the small intestine but is virtually unknown for the large bowel, although there is evidence for absorption involving Na⁺-independent anion exchange. A leading candidate is the apical chloride/bicarbonate (Cl⁻/HCO₃⁻) exchanger DRA (down-regulated in adenoma; Slc26a3), primarily linked to the Cl⁻ transporting defect in congenital chloride diarrhea. The present study set out to characterize transepithelial ³⁵SO₄²⁻ and ³⁶Cl⁻ fluxes across the isolated, short-circuited cecum from wild-type (WT) and knockout (KO) mice and subsequently to define the contribution of DRA. The cecum demonstrated simultaneous net SO₄²⁻ secretion (-8.39 ± 0.88 nmol·cm⁻²·h⁻¹) and Cl⁻ absorption (10.85 ± 1.41 μmol·cm⁻²·h⁻¹). In DRA-KO mice, SO₄²⁻ secretion was reversed to net absorption via a 60% reduction in serosal to mucosal SO₄²⁻ flux. Similarly, net Cl⁻ absorption was abolished and replaced by secretion, indicating that DRA represents a major pathway for transcellular SO₄²⁻ secretion and Cl⁻ absorption. Further experiments including the application of DIDS (500 μM), bumetanide (100 μM), and substitutions of extracellular Cl⁻ or HCO₃⁻/CO₂ helped to identify specific ion dependencies and driving forces and suggested that additional anion exchangers were operating at both apical and basolateral membranes supporting SO₄²⁻ transport. In conclusion, DRA contributes to SO₄²⁻ secretion via DIDS-sensitive HCO₃⁻/SO₄²⁻ exchange, in addition to being the principal DIDS-resistant Cl⁻/HCO₃⁻ exchanger. With DRA linked to the pathogenesis of other gastrointestinal diseases extending its functional characterization offers a more complete picture of its role in the intestine.

Mechanisms Underlying Modulation of SLC26A3 Activity by Lactobacillus acidophilus‐secreted Soluble Factors

DRA (Down‐Regulated in Adenoma, SLC26A3) mediates apical membrane Cl−/HCO3− exchange activity in mammalian intestinal epithelial cells. Our previous studies showed that soluble factor(s) in the bacteria‐free culture supernatant (CS) of the probiotic Lactobacillus acidophilus (LA) stimulated Cl−/HCO3− exchange activity in Caco‐2 cells via increasing apical membrane DRA levels. Current studies were undertaken to elucidate the mechanisms of LA‐CS enrichment of functional DRA on the apical cell surface. Post‐confluent Caco‐2 monolayers were treated for 3 h with LA‐CS. DRA function was measured as DIDS‐sensitive 125I‐uptake, surface DRA assessed by cell‐surface biotinylation/confocal microscopy. Inhibitors of PI3 kinase and Rac1, as well as methyl‐β‐D‐cyclodextran, a lipid raft‐disrupting agent, abrogated LA‐CS effects on DRA function. LA‐CS enhanced DRA levels in the detergent insoluble (DI) fraction in Caco‐2 cells. Silencing the PDZ protein NHERF2 attenuated LA‐CS enhancement of apical membrane DRA. Molecular size fractionation showed that soluble factors in the LA‐CS that enhance functional DRA on the apical membrane are of low molecular mass (3–10 kD) and are heat‐stable. Our results define novel mechanisms involving lipid rafts, NHERF, and PI3K‐Rac1 pathway in altered trafficking of DRA induced by probiotic‐secreted bioactive factor(s) to modulate intestinal chloride absorption. [Grant support: VA/NIDDK/Bill & Melinda Gates Foundation]

Preparation and characterization of poly(3-octyl thiophene)/polyvinyl chloride polymer blends

Different weight ratios of poly(3-octyl thiophene) / polyvinyl chloride blends were prepared using the casting method by dissolving poly(3-octyl thiophene) and polyvinyl chloride polymers in chloroform and Tetrahydrofuran, respectively. Fourier transform infrared spectroscopy indicates the existence of carbonyl group in both polyvinyl chloride neat and poly(3-octyl thiophene)–polyvinyl chloride blends. Electrical measurements reveal that the impedance values are increased with the increasing of both weight fraction of poly(3-octyl thiophene) and temperature. Optical results reveal that the increase of poly(3-octyl thiophene) weight fraction in blends enhances the UV-visible absorption of polyvinyl chloride and reduces the optical energy gap of blends. Differential scanning calorimetric measurements and thermal gravimetric analysis show that the glass transition temperature value and thermal stability of blend increases with increasing of poly(3-octyl thiophene) weight ratio. The obtained results, generally, indicate that the increase of poly(3-octyl thiophene) weight fraction enhances the interaction between poly(3-octyl thiophene)–polyvinyl chloride chains and as a result will restrict the chain mobility of polymers.

Solubility of Hydrogen Chloride in Three 1-Alkyl-3-methylimidazolium Chloride Ionic Liquids in the Pressure Range (0 to 100) kPa and Temperature Range (298.15 to 363.15) K

To study the possibility of using ionic liquids (ILs) as a novel solvent for the absorption of hydrogen chloride (HCl) from the industrial tail gases, the solubility of HCl gas in three ILs has been measured at four temperatures, (298.15, 323.15, 348.15, and 363.15) K, in the pressure range of (0 to 100) kPa. The ILs used are 1-butyl-3-methylimidazolium chloride ([Bmim]Cl), 1-hexyl-3-methylimidazolium chloride ([Hmim]Cl), and 1-octyl-3-methylimidazolium chloride ([Omim]Cl). The results indicate that these ILs show high solubility for HCl gas, and the solubility decreases with the increasing length of the alkyl substitutes of the ILs, following the order [Bmim]Cl > [Hmim]Cl > [Omim]Cl. The solubility of HCl in [Bmim]Cl at 298.15 K is about 0.68 mole fraction at ca. 100 kPa partial pressure of HCl, which is much higher than that of 36.5 % HCl aqueous solution. The solubility of different ILs is discussed in detail, and the experimental data (P–T–x) are correlated successfully by an empirical relation.

Enhancement by sodium caprate and sodium deoxycholate of the gastrointestinal absorption of berberine chloride in rats

The aim of the investigation was to compare the effectiveness of two absorption enhancers, sodium caprate (C10) and sodium deoxycholate (SDC), in increasing the bioavailability of a poorly absorbed paracellar flux drug, berberine chloride, across the intestinal mucosae of rats in vivo, together with examination of their effects on mucosal damage. In addition, all four intestinal segments were collected after administration of the enhancers and sodium saline. The results of the bioavailability experiments showed the oral absorption of berberine chloride was poor and both C10 and SDC could significantly improve the very poor absorption of berberine chloride. After co-administration, the area under the plasma concentration–time curve of berberine chloride was increased 41.1-fold by C10 (100 mg/kg) and 35.3-fold by SDC (100 mg/kg) compared with that in the absence of C10 and SDC, respectively. Local toxicity experiment indicated that both enhancers caused no specific damage to the intact intestine. This study demonstrates that C10 and SDC could significantly promote the absorption of berberine chloride from the gastrointestinal tract with few toxic effects, which might be due mainly to relaxing the absorption limitation while inhibiting the efflux transporter of berberine chloride by the enhancers. Besides, this could lead to the development of new drug-enhancers.

Mechanical properties and absorption of chlorides in alkali activated slag concrete and exposed to carbonation

This paper presents an experimental study on the durability properties of carbonated alkali-activated slag (AAS) concrete. An ordinary Portland cement (OPC) was also tested for comparative purposes. The durability properties were studied through the measurements of compressive strength, permeable voids, and water absorption and chloride permeation. The results indicated that the AASs showed higher compressive strength at early ages than the OPCs. Contrary, permeable voids and water absorption measurements were lower for AASs than for OPCs.

Sm2+ fluorescence and absorption in cubic BaCl2: Strong thermal crossover of fluorescence between 4f6 and 4f55d1 configurations

The optical absorption and fluorescence spectra of polycrystalline cubic-phase barium chloride doped with divalent samarium is reported. X-ray diffraction shows that the cubic phase is stabilised at room temperature by the addition of 12.5% lanthanum trichloride; no evidence for the more common orthorhombic or hexagonal phases of barium chloride is found. Optical absorption measurements are in good agreement with a calculated spectrum for Sm2+ ions at a single site of cubic symmetry, even though the material must contain a substantial fraction of chlorine interstitials and lanthanum substitutional ions. The photoluminescence spectrum shows sharp red line emission from the 5D1 and 5D0 levels of the 4f6 configuration, again consistent with a single site of cubic symmetry, together with a broad emission, also in the red, which arises from the lowest levels of the 4f55d1 configuration. The relative strengths of these emissions are strongly temperature dependent; at room temperature the broad band from the lowest 4f55d1 levels peaking at 15,130cm−1 is dominant, while at low temperature (∼12K) sharp lines from the 5D0 level dominate. The most intense line corresponds to the 5D0→7F1 transition at 14,300cm−1, but the nominally forbidden 5D0→7F0 transition also has significant intensity. The marked temperature dependence of the intensity of the lines and bands is successfully modelled by rate equations and is explained on the basis of thermally activated crossovers between the 4f6 (5D0,1) levels and the lowest levels of the 4f55d1 configuration; it is necessary to include the three lowest levels of the 4f55d1 configuration sandwiched between the 5D0 and 5D1 levels.

Chronic Diarrhea in Children

Chronic Diarrhea in Children

Experimental analysis of a solar absorption system with interior energy storage

This study examines experimentally the cooling application of a solar absorption system with interior energy storage that uses two different auxiliary systems. The experiments were performed at Uludag University, Bursa, Turkey on the 3rd and 4th of August 2010 that had the approximately same average outdoor temperature, 31°C. A solar hot water was delivered via a 40 m2 array of flat plate solar collectors that drove a lithium chloride (LiCl) absorption heat pump with a cooling power peak of 20 kW. A solar-powered air conditioning system was designed for heating and cooling in a test room that had a total floor space of 30 m2. Chilled water produced in the evaporator was supplied to the fan coil units, and the heat of condensation and absorption was rejected by means of a wet cooling tower. An electric heater and an air source heat pump were used as auxiliary systems for the absorption cooling application for two different cases when the solar energy was insufficient. Temperature variations were recorded for the absorption machine components, the test room, and the outdoors. The cooling energy, thermal energy, and daily average coefficient of performance (COP) of the absorption system were calculated for two days. Solar absorption cooling was considered for two different auxiliary systems and is presented in this manuscript. The results showed that the daily average COP of the absorption system was 0.283 for Case 1 and 0.282 for Case 2. For both cases, the interior energy storage of the absorption system enabled it to satisfy the cooling demand during the night while solar energy was not available.

Translational Approaches for Pharmacotherapy Development for Acute Diarrhea

Areport is presented of a National Institute of Diabetes and Digestive and Kidney Diseases–sponsored single topic conference designed to determine scientific advances needed to encourage development of pharmacotherapy for diarrheal diseases. Acute diarrheal diseases are a global public health problem in developing and developed countries. They are a leading cause of mortality and morbidity for children under the age of 5 worldwide and have a major economic impact in developed countries. Although oral rehydration solution (ORS) along with oral zinc therapy has reduced mortality owing to acute diarrheal diseases, there are essentially no other approved, safe, and effective drugs to decrease stool volume and prevent fluid loss. On September 25–27, 2011, the National Institute of Diabetes and Digestive and Kidney Diseases convened a workshop on Translational Approaches for Pharmacotherapy Development for Acute Diarrhea to assess current treatments for acute diarrhea, to identify common host pathways targeted by infectious agents associated with acute diarrhea, to evaluate which pathophysiologic mechanisms are most clinically relevant as potential targets, and to identify promising areas for translational research.

Study on silane impregnation for protection of high performance concrete

Steel corrosion caused by chloride penetration is the main reason for the damage of concrete structures in marine environment. By silane impregnation, the corrosion of chloride on concrete can be inhibited effectively, and the water absorption of concrete can also be decreased. Silane gel and silane solution was used as protection treatment on concrete surface respectively. Effect of silane type and painting amount of silane on the mechanical performance, capillary water absorption and chloride ion permeability of concrete was studied in the present investigation. The experimental results showed that the two silanes can penetrate to the depth of about 2∼6mm. Compared with untreated samples, the reduction of water absorption and chloride absorption of treated concrete was higher than 90%. The chloride diffusion coefficient and electric flux decreased obviously. The protection effect of silanes on concrete both improves with the increase of painting amount. The protection of silane gel on concrete was better than that of silane solution.