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1

Quaternary liquid/liquid equilibria of sodium sulfate, sodium sulfite and water with two solvents: Acetone and 2-propanol  

SciTech Connect

Aqueous solutions of sodium sulfate and sodium sulfite are produced from sodium carbonate in flue-gas scrubbers; recovery of these salts often requires multi-effect evaporators; however, a new energy-efficient unit operation called extractive crystallization has been shown to have reduced energy costs. In this process, an organic solvent is added to the aqueous salt solution to precipitate salt. Acetone is a suitable solvent for this process, better than 2-propanol. Liquid/liquid/solid equilibria for ternary systems containing a salt, water, and an organic solvent were measured. Systems investigated were sodium sulfite/water/acetone and sodium sulfite/water/2-propanol. Experiments were conducted at salt saturation covering a temperature range between the lower consolute temperature and 48.6{degrees}C. In the attempt to improve the extractive crystallization process for recovery of sodium sulfate from flue-gas scrubbers, attention was given to a feed containing a mixture of sodium sulfite and sodium sulfate. Liquid-liquid equilibria for quaternary systems containing two salts, water, and an organic solvent were experimentally determined at 35{degrees}C. The systems investigated were sodium sulfate/sodium sulfite/water/acetone and sodium sulfate/sodium sulfite/water/2propanol. The systems were studied at three salt ratios. For each salt ratio, experiments were conducted starting at saturation, water was then added until the one-phase region was reached. Mixtures of the two salts proved to have a small disadvantage relative to the 100 % sulfate feed process. Therefore, a sulfate-based extractive crystallization process is recommended.

Schiozer, A.L.

1994-03-01

2

Sulfite-sulfide-sulfate-carbonate equilibria with applications to Mars  

NASA Astrophysics Data System (ADS)

Mars volcanic SO2 and H2S gas emissions are likely the dominant source of martian sulfate, and the source of sulfuric acid. Until this work, the FREZCHEM model lacked SO2 and H2S gases and associated sulfite and sulfide minerals. The specific objectives of this paper were to add these components and associated sulfite and sulfide minerals and phases into FREZCHEM, and to explore some possible roles of these chemistries on Mars. New solid phases added included the sulfites: Na2SO3·7H2O, K2SO3, (NH4)2SO3·H2O, MgSO3·6H2O, CaSO3·0.5H2O, and FeSO3·1.5H2O, and the sulfide: FeS2. The lowest eutectic of these minerals was K2SO3 (= 6.57 m) at 228 K. Because sulfurous acid is stronger than carbonic acid, this causes a much larger fraction of S(IV) to exist as sulfite (SO32-) at acidic to mildly alkaline pH, whereas almost none of the C is present as carbonate anion. Model calculations show that small quantities of SO2 in an early CO2-rich martian atmosphere suppressed formation of carbonates because SO2 is much more water soluble than CO2 and a stronger acid, which may be a major reason why sulfates are much more common than carbonates on Mars. Also, perhaps equally important are low temperatures that favor sulfite mineral precipitation, the oxidation of which leads to sulfate minerals. Another potentially important factor that favors sulfite/sulfide mineral formation is low pH values that cannot allow carbonate minerals, but can allow sulfide minerals such as pyrite (FeS2). The presence of pyrite, highly insoluble, would lead to sulfate minerals when oxygen becomes available in acidic environments. Major cations for both sulfites (or sulfates) and carbonates (Ca and Mg) can limit carbonates. Sulfite-sulfide volcanism on a cold, lower pH, Mars are the primary causes of high sulfate minerals (e.g., Ca and Mg sulfates), compared to volcanism on a warm, higher pH, Earth that led to more abundant carbonate minerals (e.g., Ca and Mg carbonates).

Marion, G. M.; Kargel, J. S.; Crowley, J. K.; Catling, D. C.

2013-07-01

3

Nitrogen dioxide absorption in aqueous sodium sulfite  

NASA Astrophysics Data System (ADS)

The Clean Air Act of 1990 requires additional reduction of acid gases, sulfur dioxide, and nitrogen oxides released into the atmosphere from coal-fired electric power plants. In the case of older existing power plants, a possible retrofit strategy is to oxidize nitric oxide (NO, the major constituent of NOsbX in flue gas) to nitrogen dioxide (NOsb2) by the addition of methanol or other hydrocarbons into the duct at an optimum temperature regime. NOsb2 can then be removed by either modifying existing SOsb2 control equipment or by adding a limestone (CaCOsb3) slurry scrubbing process. Limestone reacts with SOsb2 to from CaSOsb3, and the free sulfite (SO{sb3sp{=}}) in the solution is reactive toward NOsb2. The focus of this research is to study the reaction between NOsb2 and aqueous sulfite at elevated temperature and in the presence of gas phase Osb2. The removal of NOsb2 by limestone slurry scrubbing involves the reaction between NOsb2 and SO{sb3sp{=}}, bisulfite (HSO{sb3sp{-}}) and water. The reactions between NOsb2 and SO{sb3sp{=}}/HSO{sb3sp{-}} are first order in both reactants, while the NOsb2-water reaction is second order in NOsb2 concentration. The rate constants of the above reactions and the NOsb2-thiosulfate (Ssb2O{sb3sp{=}}) reaction were determined at 55sp°C. SO{sb3sp{=}} was found to be the most reactive toward NOsb2, while the contribution of chemical reaction still dominated in the absorption of NOsb2 into water. The effect of gas phase SOsb2 and Osb2, and liquid phase additives such as Ssb2O{sb3sp{=}}, Casp{++}, Mgsp{++}, and Clsp{-} on NOsb2 absorption was also investigated. The absorption of NOsb2 catalyzes free radical reactions that lead to sulfite oxidation. A semi-empirical model was proposed to relate the rate of sulfite oxidation to the rate of NOsb2 absorption. Thiosulfate inhibits sulfite oxidation by providing an alternative route for the termination of the free radical reactions, and a fundamental model was derived to quantify the effect of Ssb2O{sb3sp{=}} on sulfite oxidation. The absorption of NOsb2 into aqueous bisulfide (HSsp{-}) was studied in an attempt to discover alternative scrubbing technologies. The reaction between NOsb2 and HSsp{-} is twice as fast as the NOsb2-SO{sb3sp{=}} reaction at 55sp°C. A semi-empirical model was proposed to relate NOsb2 absorption to HSsp{-} oxidation. This study has shown that acceptable level of NOsb2 removal by a conventional limestone slurry scrubber is not probable. However, aqueous scrubbing of NOsb2 by Nasb2SOsb3 and Nasb2S solutions are viable options. Furthermore, significant reduction in hold tank liquid depth and/or oxidizing air stoichiometry is possible by NOsb2 injection.

Shen, Chen Hua

4

Absorption of sulfur dioxide into aqueous sodium hydroxide and sodium sulfite solutions  

Microsoft Academic Search

The rates of absorption of pure sulfur dioxide into aqueous sodium bisulfite, sodium hydroxide, and sodium sulfite solutions with and without a surface active agent were measured at 25°C using a liquid jet column. For the sulfur dioxide-sodium hydroxide system, the rate of absorption into the solution without surface active agent was higher than that into the solution with surface

Haruo Hikita; Satoru Asai; Tadashi Tsuji

1977-01-01

5

Biochemical studies on sulfate-reducing bacteria. XIV. Enzyme levels of adenylylsulfate reductase, inorganic pyrophosphatase, sulfite reductase, hydrogenase, and adenosine triphosphatase in cells grown on sulfate, sulfite, and thiosulfate.  

PubMed

Sulfate-reducing bacteria, Desulfovibrio vulgaris, strain Miyazaki, were grown on either sulfate, sulfite, or thiosulfate as the terminal electron acceptor. Better growth was observed on sulfite and less growth on thiosulfate than on sulfate. Enzyme levels of adenylylsulfate (APS) reductase [EC 1.8.99.2], reductant-activated inorganic pyrophosphatase [EC 3.6.1.1], sulfite reductase [EC 1.8.99.1] (desulfoviridin), hydrogenase [EC 1.12.2.1], and Mg2+-activated ATPase [EC 3.6.1.3] were compared in crude extracts of these cells at various stages of growth. 1) The specific activity of APS reductase in sulfite-grown cells was only one-fourth that in sulfate-grown cells throughout growth. Thiosulfate-grown cells had an activity intermediate between those of sulfate- and sulfite-grown cells. 2) Cells grown on sulfite had lower specific activity of reductant-activated inorganic pyrophosphatase than cells grown on sulfate or thiosulfate. 3) The specific activity of sulfite reductase (desulfoviridin) was highest in sulfite-grown cells. The sulfite medium gave the enzyme in high yield as well as with high specific activity. 4) The specific activities of hydrogenase and Mg2+-ATPase were not significantly altered by electron acceptors in the growth medium. PMID:175050

Kobayashi, K; Morisawa, Y; Ishituka, T; Ishimoto, M

1975-11-01

6

21 CFR 186.1797 - Sodium sulfate.  

Code of Federal Regulations, 2010 CFR

...RECOGNIZED AS SAFE Listing of Specific Substances Affirmed as GRAS § 186.1797 Sodium sulfate. (a) Sodium sulfate (Na2 SO4 , CAS Reg. No. 7757-82-6), also known as Glauber's salt, occurs naturally and exists as colorless...

2010-04-01

7

THE REACTION RATE OF SODIUM SULFITE WITH DISSOLVED OXYGEN. Technical Report No. 73  

Microsoft Academic Search

The reaction rate of sodium sulfite was studied as a function of oxygen ;\\u000a concentration, NaâSOâ\\/Oâ ratio, temperature, catalyst, pH and ;\\u000a surface\\/volume ratio.The reaction rate of hydrazine with dissolved oxygen was ;\\u000a also studied. Oxygen removal is incomplete when the sulfite to oxygen ratio is ;\\u000a leas than the stoichiometric quantity. With the stoichiometric quantities of ;\\u000a oxygen and

1960-01-01

8

40 CFR 415.170 - Applicability; description of the sodium dichromate and sodium sulfate production subcategory.  

...Applicability; description of the sodium dichromate and sodium sulfate production subcategory...MANUFACTURING POINT SOURCE CATEGORY Sodium Dichromate and Sodium Sulfate Production Subcategory...Applicability; description of the sodium dichromate and sodium sulfate production...

2014-07-01

9

21 CFR 182.1131 - Aluminum sodium sulfate.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Aluminum sodium sulfate. 182.1131 Section 182...Purpose GRAS Food Substances § 182.1131 Aluminum sodium sulfate. (a) Product. Aluminum sodium sulfate. (b) Conditions of...

2012-04-01

10

21 CFR 582.1131 - Aluminum sodium sulfate.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Aluminum sodium sulfate. 582.1131 Section 582...General Purpose Food Additives § 582.1131 Aluminum sodium sulfate. (a) Product. Aluminum sodium sulfate. (b) Conditions of...

2012-04-01

11

FT Raman investigation of sodium cellulose sulfate  

Microsoft Academic Search

FT Raman investigation of sodium cellulose sulfates (NaCS) was reported. Different NaCS were prepared by two diverse sulfation\\u000a methods and their total degrees of substitution (DS) of sulfate groups were determined through either 13C-NMR spectroscopy or elemental analysis. Subsequently, these NaCS were characterized with FT Raman spectroscopy. The caused\\u000a bands through the introduction of the sulfate groups in cellulose chain

Kai Zhang; Erica Brendler; Steffen Fischer

2010-01-01

12

The Escherichia coli CysZ is a pH dependent sulfate transporter that can be inhibited by sulfite.  

PubMed

The Escherichia coli inner membrane protein CysZ mediates the sulfate uptake subsequently utilized for the synthesis of sulfur-containing compounds in cells. Here we report the purification and functional characterization of CysZ. Using Isothermal Titration Calorimetry, we have observed interactions between CysZ and its putative substrate sulfate. Additional sulfur-containing compounds from the cysteine synthesis pathway have also been analyzed for their abilities to interact with CysZ. Our results suggest that CysZ is dedicated to a specific pathway that assimilates sulfate for the synthesis of cysteine. Sulfate uptake via CysZ into E. coli whole cells and proteoliposome offers direct evidence of CysZ being able to mediate sulfate uptake. In addition, the cysteine synthesis pathway intermediate sulfite can interact directly with CysZ with higher affinity than sulfate. The sulfate transport activity is inhibited in the presence of sulfite, suggesting the existence of a feedback inhibition mechanism in which sulfite regulates sulfate uptake by CysZ. Sulfate uptake assays performed at different extracellular pH and in the presence of a proton uncoupler indicate that this uptake is driven by the proton gradient. PMID:24657232

Zhang, Li; Jiang, Wangshu; Nan, Jie; Almqvist, Jonas; Huang, Yafei

2014-07-01

13

The oxygen isotope signature of sulfate derived from abiotic sulfite oxidation under different pH conditions  

NASA Astrophysics Data System (ADS)

The oxygen isotope composition of sulfate serves as an archive of past oxidative sulfur cycling. It carries information about the oxidants as well as the biochemical pathway involved in the oxidation of reduced sulfur compounds, because oxygen sources can be traced by their distinct oxygen isotope composition. Studies on the aerobic oxidation of pyrite determined varying relative contributions of oxygen from dissolved molecular oxygen (O2) and water (H2O). These discrepancies were assumed to be due to slight differences in the production and consumption of sulfur intermediates which can exchange oxygen isotopes with water. Additionally, changing pH conditions influence the oxidation rate of sulfur intermediates to sulfate as well as the rate of oxygen exchange between sulfur intermediates and water. Consequently, this affects the oxygen isotope signature of produced sulfate. However, very little is known about the oxygen isotope effects during the oxidation of sulfur intermediates. We performed experiments to assess the abiotic oxidation of sulfite to sulfate under different pH conditions, as sulfite is assumed to be an intermediate during the oxidation of reduced sulfur compounds. Dissolved sulfite was oxidized with differently isotopically labeled O2, as well as in differently labeled H2O. The relative contribution of oxygen from O2 and water in produced sulfate was determined, along with the respective oxygen isotope fractionation. Our results provide a more detailed mechanistic understanding of the aerobic oxidation of reduced sulfur species.

Mueller, I.; Brunner, B.; Ferdelman, T. G.

2011-12-01

14

Nitrogen Dioxide Absorption and Sulfite Oxidation in Aqueous Sulfite  

E-print Network

Nitrogen Dioxide Absorption and Sulfite Oxidation in Aqueous Sulfite C H E N H . S H E N A N D G absorption into aqueous sodium sulfite and bisulfite solutions, both in a gas liquid contactor and a spray by absorption in sulfite solution in existing scrubbers for desulfurization. Rates of NO2 absorption and sulfite

Rochelle, Gary T.

15

Sodium zinc hydroxide sulfite with a novel Zn3OH geometry.  

PubMed

The synthesis and crystal structure of a new sodium zinc hydroxide sulfite, Na[(Zn(OH)]3(SO3)2, with novel structural features and bonding geometry are reported. In Na[(Zn(OH)]3(SO3)2, Zn2+ and O2- alternate to form an interesting corrugated hexagonal sheet with rings consisting of (ZnO)3. Another rare occurrence is the bonding geometry of one-third of the O sites within the sheet. These O sites form a planar Zn3O unit, unlike other known compounds, in which Zn3O is pyramidal. PMID:17173386

Nguyen, Dan-Tam; Bu, Xianhui

2006-12-25

16

Effects of sulfhydryl compounds, carbohydrates, organic acids, and sodium sulfite on the formation of lysinoalanine in preserved egg.  

PubMed

To identify inhibitors for lysinoalanine formation in preserved egg, sulfhydryl compounds (glutathione, L-cysteine), carbohydrates (sucrose, D-glucose, maltose), organic acids (L-ascorbic acid, citric acid, DL-malic acid, lactic acid), and sodium sulfite were individually added at different concentrations to a pickling solution to prepare preserved eggs. Lysinoalanine formation as an index of these 10 substances was determined. Results indicate that glutathione, D-glucose, maltose, L-ascorbic acid, citric acid, lactic acid, and sodium sulfite all effectively diminished lysinoalanine formation in preserved egg albumen and yolk. When 40 and 80 mmol/L of sodium sulfite, citric acid, L-ascorbic acid, and D-glucose were individually added into the pickling solution, the inhibition rates of lysinoalanine in the produced preserved egg albumen and yolk were higher. However, the attempt of minimizing lysinoalanine formation was combined with the premise of ensuring preserved eggs quality. Moreover, the addition of 40 and 80 mmol/L of sodium sulfite, 40 and 80 mmol/L of D-glucose, 40 mmol/L of citric acid, and 40 mmol/L of L-ascorbic acid was optimal to produce preserved eggs. The corresponding inhibition rates of lysinoalanine in the albumen were approximately 76.3% to 76.5%, 67.6% to 67.8%, 74.6%, and 74.6%, and the corresponding inhibition rates of lysinoalanine in the yolk were about 68.7% to 69.7%, 50.6% to 51.8%, 70.4%, and 57.8%. It was concluded that sodium sulfite, D-glucose, L-ascorbic, and citric acid at suitable concentrations can be used to control the formation of lysinoalanine during preserved egg processing. PMID:25047093

Luo, Xu-Ying; Tu, Yong-Gang; Zhao, Yan; Li, Jian-Ke; Wang, Jun-Jie

2014-08-01

17

Enhanced generation of hydroxyl radical and sulfur trioxide anion radical from oxidation of sodium sulfite, nickel(II) sulfite, and nickel subsulfide in the presence of nickel(II) complexes.  

PubMed Central

Electron spin resonance (ESR) spin trapping was utilized to investigate the generation of free radicals from oxidation of sodium sulfite, nickel(II) sulfite, and nickel subsulfide (Ni3S2) by ambient oxygen or H2O2 at pH 7.4. The spin trap used was 5,5-dimethyl-1-pyrroline-N-oxide (DMPO). Under ambient oxygen, a solution of sodium sulfite alone generated predominantly sulfur trioxide anion radical (.SO3-) due to the autoxidation of sulfite. Addition of nickel(II) chloride [Ni(II)] enhanced the .SO3- yield about 4-fold. Incubation of sulfite with Ni(II) in the presence of chelators such as tetraglycine, histidine, beta-alanyl-3-methyl-L-histidine (anserine), beta--L-histidine (carnosine), gamma-aminobutyryl-L-histidine (homocarnosine), glutathione, and penicillamine did not have any significant effect on that enhancement. In contrast, albumin, and especially glycylglycylhistidine (GlyGlyHis), augmented the enhancing effect of Ni(II) by factors of 1.4 and 4, respectively. Computer simulation analysis of the spin-adduct spectrum and formate scavenging experiment showed that the mixture of sodium sulfite, Ni(II), and GlyGlyHis generated both hydroxyl (.OH) radical and .SO3- radical, in the ratio of approximately 1:2. The free-radical spin adduct intensity reached its saturation level in about 5 min. The yield of the radical adducts could be slightly reduced by deferoxamine and very strongly reduced by diethylenetriaminepentaacetic acid (DTPA). Aqueous suspensions of sparingly soluble nickel(II) sulfite in the presence of air and GlyGlyHis generated surface-located .SO3- and .OH radicals. The same radicals were generated in Ni3S2 suspension in the presence of GlyGlyHis and H2O2, indicating sulfite production by oxidation of the sulfide moiety of this compound.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7843142

Shi, X; Dalal, N; Kasprzak, K S

1994-01-01

18

Adsorption of Sodium Dodecyl Sulfate and Sodium Dodecyl Benzenesulfonate on Poly(Vinyl Chloride) Latexes  

E-print Network

1 Adsorption of Sodium Dodecyl Sulfate and Sodium Dodecyl Benzenesulfonate on Poly(Vinyl Chloride@cpe.fr #12;2 Abstract The adsorption of sodium dodecyl sulfate (SDS) and sodium dodecyl benzenesulfonate (SDBS) on poly(vinyl chloride) (PVC) latex particles was investigated. Conductometric titrations were

Paris-Sud XI, Université de

19

Sodium dodecyl sulfate micelles in polyacrylamide gels.  

NASA Astrophysics Data System (ADS)

Polyacrylamide gels have been made in the presence of sodium dodecyl sulfate (SDS) micelles. The use of these gels for electrophoresis, after removal of the SDS, has demonstrated that the micelles modify the internal gel structure(R. Rill, B. Locke, Y. Liu, J. Dharia, D Van Winkle, Electrophoresis 17), 1304 (1996).. The phase diagram of SDS in buffer exhibits several transitions as a function of concentration and ionic strength. The SDS concentration used for templating gels is quite high, on the order of 20 - 30% by weight. This is the range in which the micellar system undergoes phase transitions. X-ray and light scattering experiments on gels with and without SDS and in SDS-buffer solutions were performed to understand the structure of the templated pores left after SDS removal. These experiments indicate the characteristic length scales associated with SDS micelles in gels changes from 3 to 15 nm as the gel and the SDS concentrations are varied.

van Winkle, David H.; Kettwig, Franz; Rill, Randolph L.; Liu, Yingjie; Locke, Bruce R.

1997-03-01

20

The crystal structure of Desulfovibrio vulgaris dissimilatory sulfite reductase bound to DsrC provides novel insights into the mechanism of sulfate respiration.  

PubMed

Sulfate reduction is one of the earliest types of energy metabolism used by ancestral organisms to sustain life. Despite extensive studies, many questions remain about the way respiratory sulfate reduction is associated with energy conservation. A crucial enzyme in this process is the dissimilatory sulfite reductase (dSiR), which contains a unique siroheme-[4Fe4S] coupled cofactor. Here, we report the structure of desulfoviridin from Desulfovibrio vulgaris, in which the dSiR DsrAB (sulfite reductase) subunits are bound to the DsrC protein. The alpha(2)beta(2)gamma(2) assembly contains two siroheme-[4Fe4S] cofactors bound by DsrB, two sirohydrochlorins and two [4Fe4S] centers bound by DsrA, and another four [4Fe4S] centers in the ferredoxin domains. A sulfite molecule, coordinating the siroheme, is found at the active site. The DsrC protein is bound in a cleft between DsrA and DsrB with its conserved C-terminal cysteine reaching the distal side of the siroheme. We propose a novel mechanism for the process of sulfite reduction involving DsrAB, DsrC, and the DsrMKJOP membrane complex (a membrane complex with putative disulfide/thiol reductase activity), in which two of the six electrons for reduction of sulfite derive from the membrane quinone pool. These results show that DsrC is involved in sulfite reduction, which changes the mechanism of sulfate respiration. This has important implications for models used to date ancient sulfur metabolism based on sulfur isotope fractionations. PMID:18829451

Oliveira, Tânia F; Vonrhein, Clemens; Matias, Pedro M; Venceslau, Sofia S; Pereira, Inês A C; Archer, Margarida

2008-12-01

21

Protective performances of two anti-graffiti treatments towards sulfite and sulfate formation in SO 2 polluted model environment  

NASA Astrophysics Data System (ADS)

Specific strategies for protection are being developed to counter both the staining and corrosive effects of polluted air in cities, as well as to allow for efficient removal of unwanted graffiti paintings. These protection strategies employ molecules with tailored functionalities, e.g. being hydrophobic, while maintaining porosity for molecular water vapour permeation. The present study employs SO 2 and water to probe the behaviors of two anti-graffiti treatments, a water-base fluoroalkylsiloxane ("Protectosil Antigraffiti" marketed by Degussa) and an organically modified silicate (Ormosil) synthesized from a polymer chain (polydimethyl siloxane, PDMS) and two network forming alkoxides (Zr propoxide and methyl triethoxy silane, MTES) dissolved in n-propanol, on five building materials, comprising limestone, aged lime mortar, hydrated cement mortar, granite, and brick material. The materials were exposed to a synthetic atmosphere for 20 h in a climate chamber, 0.78 ± 0.03 ppm of SO 2 and 95% RH. Diffuse reflectance Fourier transform infrared (DR-FTIR) spectra were registered before and after exposure in the climate chamber in the cases of both treated and untreated samples. DR-FTIR, scanning electron microscope (SEM) images and energy dispersive X-ray (EDX) analyses, suggest the anti-graffiti Ormosil to suppress formation of calcium sulfite hemihydrate (the primary initial product of the reaction of calcium compounds with SO 2 and water) on carbonate materials (limestone and lime mortar). In case of the granite, brick and cement mortar, Ormosil has a negligible influence on the SO 2 capture. While no sulfite formation was detected by DR-FTIR, gypsum is inferred to form due to metal oxides and minority compounds catalysed oxidation of sulfite to sulfate. In case of brick, this understanding finds support from SEM images as well as EDX. A priori presence of gypsum in hydrated cement mortars prevents positive identification by SEM. However, support for sulfur accumulation in hydrated cement mortar is provided by means of EDX. In case of a second anti-graffiti considered, Protectosil, no influence of the anti-graffiti treatment on the SO 2 uptake of any of the building materials was observed.

Carmona-Quiroga, Paula María; Panas, Itai; Svensson, Jan-Erik; Johansson, Lars-Gunnar; Blanco-Varela, María Teresa; Martínez-Ramírez, Sagrario

22

Sulfur speciation by capillary zone electrophoresis. Determination of dithionite and its decomposition products sulfite, sulfate and thiosulfate in commercial bleaching agents.  

PubMed

In this paper, a capillary zone electrophoretic (CZE) method was developed for the separation of the sulfur species dithionite (S2O4(2-)), sulfite (SO3(2-)), sulfate (SO4(2-)) and thiosulfate (S2O3(2-)). A carrier electrolyte (pH 7.0) containing 1.5 mmol L(-1) pyromellitic (PM) acid, 10 mmol L(-1) Tris(hydroxymethyl)-aminomethane (Tris), 0.5 mmol L(-1) diethylenetriamine (DETA) and 0.1% (v/v) formaldehyde (as stabilizer for S2O4(2-) and SO3(2-)) allowed the determination of the sulfur anions after 9 min CZE separation with indirect UV detection at 214 nm. The addition of 0.1% (v/v) formaldehyde to the sample solution stabilizes dithionite and sulfite as HOCH2SO2- and HOCH2SO3- anions. The procedure was applied for the determination of dithionite and its decomposition products sulfite, sulfate and thiosulfate in commercial formulations of bleaching agents. Dithionite was found to be the major component of the commercial formulations in concentrations between 30.80 and 33.30% (w/w). As anticipated, sulfite, sulfate and thiosulfate were found to be present as decomposition or by-products in the commercial formulations at concentrations of 14.30-14.80, 5.20-5.70 and 0.30-0.40% (w/w), respectively. The results were found to be in good agreement with those of polarographic and spectrophotometric determinations. PMID:16330279

de Carvalho, Leandro M; Schwedt, Georg

2005-12-16

23

Sodium sulfate - Vaporization thermodynamics and role in corrosive flames  

NASA Technical Reports Server (NTRS)

Mass spectrometer experiments were conducted to determine the thermodynamic properties of gaseous Na2SO4, and these data were used in a computer program to calculate equilibrium flame compositions and temperatures for representative turbine engine and burner rig flames. The work is important in that sodium sulfate is the major phase recovered from turbine surfaces after instances of corrosion, due to the presence of sulfur in fuels and sodium chloride in intake air.

Kohl, F. J.; Stearns, C. A.; Fryburg, G. C.

1975-01-01

24

Mechanism for forming hydrogen chloride and sodium sulfate from sulfur trioxide, water, and sodium chloride  

NASA Technical Reports Server (NTRS)

A molecular orbital study of sodium sulfate and hydrogen chloride formation from sulfur trioxide, water, and sodium chloride shows no activation barrier, in agreement with recent experimental work of Kohl, Fielder, and Stearns. Two overall steps are found for the process. First, gas-phase water reacts with sulfur trioxide along a pathway involving a linear O-H-O transition state yielding closely associated hydroxyl and bisulfite which rearrange to become a hydrogen sulfate molecule. Then the hydrogen sulfate molecule transfers a hydrogen atom to a surface chloride in solid sodium chloride while an electron and a sodium cation simultaneously transfer to yield sodium bisulfate and gas-phase hydrogen chloride. This process repeats. Both of these steps represent well-known reactions for which mechanisms have not been previously determined.

Anderson, A. B.

1984-01-01

25

Mechanism for forming hydrogen chloride and sodium sulfate from sulfur trioxide, water, and sodium chloride  

SciTech Connect

A molecular orbital study of sodium sulfate and hydrogen chloride formation from sulfur trioxide, water, and sodium chloride shows no activation barrier, in agreement with recent experimental work of Kohl, Fielder, and Stearns. Two overall steps are found for the process. First, gas-phase water reacts with sulfur trioxide along a pathway involving a linear O...H...O transition state yielding closely associated hydroxyl and bisulfite which rearrange to become a hydrogen sulfate molecule. Then the hydrogen sulfate molecule transfers a hydrogen atom to a surface chloride in solid sodium chloride while an electron and a sodium cation simultaneously transfer to yield sodium bisulfate and gas-phase hydrogen chloride. This process repeats. Both of these steps represent well-known reactions for which mechanisms have not been previously determined.

Anderson, A.B.

1984-10-17

26

Enhanced growth of methane-propane clathrate hydrate crystals with sodium dodecyl sulfate, sodium tetradecyl sulfate, and sodium hexadecyl sulfate surfactants  

NASA Astrophysics Data System (ADS)

In the present study the effect of three commercially available anionic surfactants on the hydrate growth from a gas mixture of 90.5 mol% methane/9.5 mol% propane mixture was investigated. The surfactants used were sodium dodecyl sulfate (SDS), sodium tetradecyl sulfate (STS), and sodium hexadecyl sulfate (SHS). The morphology of the growing crystals and the gas consumption were observed during the experiments. The results showed that in the presence of surfactants, branches of porous fibre-like crystals were formed instead of dendritic crystals formed in the absence of any additive. In addition, extensive hydrate crystal growth on the crystallizer walls and a "mushy" hydrate layer instead of a thin crystal film appeared at the gas/water interface. Finally, the addition of SDS with concentration range between 242 and 2200 ppm (? T=13.1 K) was found to increase the mole consumption for hydrate formation by approximately 14 times compared to pure water. This increase is related to the change in hydrate morphology, whereby a more porous hydrate forms with enhanced water/gas contacts.

Yoslim, Jeffry; Linga, Praveen; Englezos, Peter

2010-12-01

27

21 CFR 186.1797 - Sodium sulfate.  

...Na2 SO4 , CAS Reg. No. 7757-82-6), also known as Glauber's salt, occurs naturally and exists as colorless crystals or as a fine, white crystalline powder. It is prepared by the neutralization of sulfuric acid with sodium...

2014-04-01

28

21 CFR 186.1797 - Sodium sulfate.  

Code of Federal Regulations, 2012 CFR

...Na2 SO4 , CAS Reg. No. 7757-82-6), also known as Glauber's salt, occurs naturally and exists as colorless crystals or as a fine, white crystalline powder. It is prepared by the neutralization of sulfuric acid with sodium...

2012-04-01

29

Polymerization of styrene initiated by a novel initiator sodium formaldehyde sulfoxylate and sodium lauryl sulfate  

Microsoft Academic Search

Sodium formaldehyde sulfoxylate (SFS) along with sodium lauryl sulfate (SLS) was used as a novel initiator for aqueous polymerization of styrene (St) at 80°C. The rather stable emulsion lattices and a uniform size distribution of lattice particles were obtained. The polymerization behaviors and the qualities of the product were determined. The course of polymerization is similar to the traditional emulsion

Cheng-Chien Wang; Jen-Feng Kuo; Chuh-Yung Chen

2000-01-01

30

Sodium-sulfate/carboxylate cotransporters (SLC13).  

PubMed

The SLC13 gene family is comprised of five sequence related proteins that are found in animals, plants, yeast and bacteria. Proteins encoded by the SLC13 genes are divided into the following two groups of transporters with distinct anion specificities: the Na(+)-sulfate (NaS) cotransporters and the Na(+)-carboxylate (NaC) cotransporters. Members of this gene family (in ascending order) are: SLC13A1 (NaS1), SLC13A2 (NaC1), SLC13A3 (NaC3), SLC13A4 (NaS2) and SLC13A5 (NaC2). SLC13 proteins encode plasma membrane polypeptides with 8-13 putative transmembrane domains, and are expressed in a variety of tissues. They are all Na(+)-coupled symporters with strong cation preference for Na(+), and insensitive to the stilbene 4, 4'-diisothiocyanatostilbene-2, 2'-disulphonic acid (DIDS). Their Na(+):anion coupling ratio is 3:1, indicative of electrogenic properties. They have a substrate preference for divalent anions, which include tetra-oxyanions for the NaS cotransporters or Krebs cycle intermediates (including mono-, di- and tricarboxylates) for the NaC cotransporters. This review will describe the molecular and cellular mechanisms underlying the biochemical, physiological and structural properties of the SLC13 gene family. PMID:23177988

Markovich, Daniel

2012-01-01

31

Adhesive properties of soy proteins modified by sodium dodecyl sulfate and sodium dodecylbenzene sulfonate  

Microsoft Academic Search

A study was conducted on adhesive and water-resistance properties of soy protein isolates modified by sodium dodecyl sulfate\\u000a (SDS) (0.5, 1, and 3%) and sodium dodecylbenzene sulfonate (SDBS) (0.5, 1, and 3%) and applied on walnut, cherry, and pine\\u000a plywoods. Soy proteins modified by 0.5 and 1% SDS showed greater shear strengths than did unmodified protein. One percent\\u000a SDS modification

Weining Huang; Xiuzhi Sun

2000-01-01

32

Destabilization of yttria-stabilized zirconia induced by molten sodium vanadate-sodium sulfate melts  

NASA Technical Reports Server (NTRS)

The extent of surface destabilization of ZrO2 - 8 wt percent Y2O3 ceramic disks was determined after exposure to molten salt mixtures of sodium sulfate containing up to 15 mole percent sodium metavanadate (NaVO3) at 1173 K. The ceramic surface was observed to transform from the cubic/tetragonal to monoclinic phase, concurrent with chemical changes in the molten salt layer in contact with the ceramic. Significant attack rates were observed in both pure sulfate and metavanadate sulfate melts. The rate of attack was found to be quite sensitive to the mole fraction of vanadate in the molten salt solution and the partial pressure of sulfur trioxide in equilibrium with the salt melt. The observed parabolic rate of attack is interpreted to be caused by a reaction controlled by diffusion in the salt that penetrates into the porous layer formed by the destabilization. The parabolic rate constant in mixed sodium metavanadate - sodium sulfate melts was found to be proportional to the SO3 partial pressure and the square of the metavanadate concentration. In-situ Raman spectroscopic measurements allowed simultaneous observations of the ceramic phases and salt chemistry during the attack process.

Nagelberg, A. S.; Hamilton, J. C.

1985-01-01

33

Physicochemical effects on sulfite transformation in a lipid-rich Chlorella sp. strain  

NASA Astrophysics Data System (ADS)

SO2 is very rapidly hydrated to sulfurous acid in water solution at pH value above 6.0, whereby sulfite is yielded from the disassociation of protons. We aimed to improve the sulfite transformation efficiency and provide a basis for the direct utilization of SO2 from flue gas by a microalgal suspension. Chlorella sp. XQ-20044 was cultured in a medium with 20 mmol/L sodium sulfite under different physicochemical conditions. Under light conditions, sulfite concentration in the algal suspension reduced linearly over time, and was completely converted into sulfate within 8 h. The highest sulfite transformation rate (3.25 mmol/(L·h)) was obtained under the following conditions: 35°C, light intensity of 300 ?mol/(m2·s), NaHCO3 concentration of 6 g/L, initial cell density (OD540) of 0.8 and pH of 9-10. There was a positive correlation between sulfite transformation rate and the growth of Chlorella, with the conditions favorable to algal growth giving better sulfite transformation. Although oxygen in the air plays a role in the transformation of SO2- 3 to SO2- 4, the transformation is mainly dependent on the metabolic activity of algal cells. Chlorella sp. XQ-20044 is capable of tolerating high sulfite concentration, and can utilize sulfite as the sole sulfur source for maintaining healthy growth. We found that sulfite ?20 mmol/L had no obvious effect on the total lipid content and fatty acid profiles of the algae. Thus, the results suggest it is feasible to use flue gas for the mass production of feedstock for biodiesel using Chlorella sp. XQ-20044, without preliminary removal of SO2, assuming there is adequate control of the pH.

Liang, Fang; Wen, Xiaobin; Luo, Liming; Geng, Yahong; Li, Yeguang

2014-11-01

34

Amperometric Determination of Sulfite by Gas Diffusion-Sequential Injection with Boron-Doped Diamond Electrode  

PubMed Central

A gas diffusion sequential injection system with amperometric detection using a boron-doped diamond electrode was developed for the determination of sulfite. A gas diffusion unit (GDU) was used to prevent interference from sample matrices for the electrochemical measurement. The sample was mixed with an acid solution to generate gaseous sulfur dioxide prior to its passage through the donor channel of the GDU. The sulfur dioxide diffused through the PTFE hydrophobic membrane into a carrier solution of 0.1M phosphate buffer (pH 8)/0.1% sodium dodecyl sulfate in the acceptor channel of the GDU and turned to sulfite. Then the sulfite was carried to the electrochemical flow cell and detected directly by amperometry using the boron-doped diamond electrode at 0.95 V (versus Ag/AgCl). Sodium dodecyl sulfate was added to the carrier solution to prevent electrode fouling. This method was applicable in the concentration range of 0.2-20 mg SO32?/L and a detection limit (S/N = 3) of 0.05 mg SO32?/L was achieved. This method was successfully applied to the determination of sulfite in wines and the analytical results agreed well with those obtained by iodimetric titration. The relative standard deviations for the analysis of sulfite in wines were in the range of 1.0-4.1 %. The sampling frequency was 65 h?1.

Chinvongamorn, Chakorn; Pinwattana, Kulwadee; Praphairaksit, Narong; Imato, Toshihiko; Chailapakul, Orawon

2008-01-01

35

Molecular Dynamics Simulations of Sodium Dodecyl Sulfate Micelle in Water: The Behavior of Water  

E-print Network

Molecular Dynamics Simulations of Sodium Dodecyl Sulfate Micelle in Water: The Behavior of Water dynamics simulation of a 60 monomer sodium dodecyl sulfate micellar system containing 7579 TIP3P water molecules, the behavior of water in different electrostatic environments was examined. Structural evaluation

Perera, Lalith

36

Growth of Enterobacter cloacae in the presence of 25% sodium dodecyl sulfate.  

PubMed Central

The growth of Enterobacter cloacae in 25% sodium dodecyl sulfate is described. The bacteria appeared to tolerate sodium dodecyl sulfate rather than metabolize it. The process was energy dependent, and cell lysis occurred during stationary phase. Extreme detergent resistance may be characteristic of the genus Enterobacter. PMID:7447446

Kramer, V C; Calabrese, D M; Nickerson, K W

1980-01-01

37

Instrumental methods of analysis of sulfur compounds in synfuel process streams. Quarterly technical progress report for April-June 1984. [Sulfidic, polysulfidic, thiosulfate, sulfite, sulfate, thiocyanate  

SciTech Connect

Task 1: methods development for the speciation of the polysulfides. Work on this task has been completed in December 1983 and reported accordingly in DOE/PC/40783-T13. Task 2: methods development for the speciation of dithionite and polythionates. Electrochemical reduction of tetrathionate and pentathionate at the dropping mercury electrode (DME) proceeds through a mechanism involving specific adsorption of the reactant at the DME surface and yielding polarographic waves at -0.2 volt (versus the saturated calomel electrode) in aqueous solution. Ethanol interferes with the specific adsorption of tetrathionate and pentathionate in a range of potentials between 0.0 and -1.1 volt, because EtOH is preferentially adsorbed. This results in a shift of the polarographic half-wave potentials of tetrathionate and pentathionate, which facilitates their determination in polythionate mixtures. On the other hand, the polarographic reduction of trithionate is unaffected by ethanol, because it occurs at -1.5 volt where ethanol is not adsorbed at the surface of the DME. Task 3: total accounting of the sulfur balance in representative samples of synfuel process streams. Analyses of two aqueous gasifier effluents from Grand Forks, ND, were performed. An untreated specimen contained sulfidic and polysulfidic sulfur, thiosulfate and thiocyanate. On the other hand, sulfite, sulfate, and thiocyanate were the only sulfur moieties observed in the Grand Forks sample which had been stripped at PETC. 7 references, 1 figure, 3 tables.

Jordan, J.; Sexton, E.; Talbott, J.; Yakupkovic, J.

1984-07-01

38

Durability of sodium sulfate-treated polylysine-alginate microcapsules.  

PubMed

Chelated hollow microcapsules are unstable under in vitro conditions because of their hygroscopic nature. Nongel inducing cations, such as Na+, stabilize the outer membrane of the alginate-polylysine-alginate microcapsules leading to more stable beads. We made different batches of empty capsules with a mean +/- SEM diameter of 607+/-11 microns, and found that within 1 week of incubating these capsules in normal saline at 37 degrees C, they increased to 718+/-10 microns (p < 0.05, n = 5). In initial experiments, we made different batches of capsules and divided them into two groups. One group was left untreated (control) whereas the other was treated with 6 mM Na2SO4 for 30 min, before incubation in saline at 37 degrees C. Control capsules increased in weight and size, before beginning to melt in less than 1 week. In contrast, treated capsules rapidly lost weight and remained intact during 1 month of follow-up. In perifusion experiments, we found no deleterious effect of sodium sulfate treatment on the function of islets enclosed in the capsules. PMID:11189046

Darrabie, M; Freeman, B K; Kendall, W F; Hobbs, H A; Opara, E C

2001-03-01

39

Multiphasic Kinetics of Myoglobin/Sodium Dodecyl Sulfate Complex Formation  

PubMed Central

We have carried out a kinetic analysis of the conformational changes that myoglobin (Mb) undergoes in the presence of the anionic surfactant sodium dodecyl sulfate (SDS). The time-resolved results have been combined with steady-state circular dichroism (CD) and resonance Raman (RR) spectroscopy. Time-resolved absorption spectra indicate that SDS induces changes in the heme coordination with the formation of three different Mb species, depending on SDS concentration. The formation of the Mb/SDS complex involves three or four phases, depending on surfactant concentration. The kinetic data are analyzed assuming two modes of interaction according to whether SDS is monomeric or micellar. The two pathways are separated but interconnected through free Mb. At the lowest concentrations a six-coordinated, low-spin form dominates. Two distinct five-coordinated species are formed at higher SDS concentrations: one is a protein-free heme and the other reequilibrates slowly with the six-coordinated, low-spin form. The resulting complexes have been characterized by CD and RR. In addition, CD spectra show that the local changes in the heme environment are coupled to changes in the protein structure. PMID:17369406

Feis, Alessandro; Tofani, Luca; De Sanctis, Giampiero; Coletta, Massimo; Smulevich, Giulietta

2007-01-01

40

Abiotic Oxygen Isotope Equilibrium Fractionation Between Sulfite and Water  

NASA Astrophysics Data System (ADS)

Sulfite (SO32-) is an important intermediate in biochemical transformations of sulfur compounds. Biological pathways as diverse as sulfate reduction, disproportionation of elemental sulfur and thiosulfate and sulfide oxidation can involve sulfite as intermediate compound. Unlike sulfate, sulfite readily exchanges oxygen isotopes with water. Therefore, the oxygen isotope composition of sulfate produced by the oxidation of sulfite may be controlled to a large extent by the oxygen isotope signature inherited from sulfite. While there is a lot of speculation in how far oxygen isotope exchange between sulfite and water controls the oxygen isotope composition of sulfate from seawater, interstitial waters and brines, the actual equilibrium isotope fractionation factor between sulfite and water has not yet been determined by a direct experiment. Here, we present the first results of experiments, where we equilibrated sulfite with water for several weeks at 4, 25 and 70 C at a pH of 7.2 and 8. Compared to water at pH 7.2, sulfite is enriched in 18O by 12.7±1‰ (4 C), 11.5±1‰ (23 C) and 10.3±1‰ (70 C). At pH 8, sulfite is enriched in 18O by 9.8±1‰ (4 C), 7.9±1‰ (23 C) and 6.0±1‰ (70 C) compared to water. The dependency of the fractionation on pH could either be due to an incomplete oxygen isotope exchange between water and sulfite at high pH or due to two different equilibrium oxygen isotope fractionations in the system water - bisulfite (HSO3-) - sulfite (SO32-). Our results imply that in biochemical pathways such as sulfate reduction and disproportionation, oxygen isotope exchange between sulfite and water is not the dominant factor controlling the oxygen isotope composition of sulfate.

Brunner, B.; Mielke, R. E.; Coleman, M.

2006-12-01

41

Bioenergetic effects of sodium sulfate on the freshwater crustacean, Ceriodaphnia dubia  

Microsoft Academic Search

I tested the hypothesis that if sodium sulfate alters the bioenergetics of Ceriodaphnia dubia, concentrations that cause reduced fecundity in the short (7-day) and long (5 generations) term should also cause changes\\u000a in feeding rate and\\/or metabolism, measured as oxygen consumption. In addition, to test the hypothesis that an altered bioenergetic\\u000a level caused by sodium sulfate exposure will affect the

David J. Soucek

2007-01-01

42

2,4,6-trinitrophenyl-amino acid derivatives as spectrophotometric reagents for sulfur dioxide. [Using sodium sulfite  

SciTech Connect

A spectrophotometric method for sulfur dioxide determination was explored on the basis of its complexation with TNP-amino acid derivatives forming an orange colored 1:1 complex with an increase in absorbance at 420 nm. TNP-glycine, TNP-threonine, TNP-serine and TNP-histidine (TNP-(2,4,6-trinitrophenyl-)) were investigated. The color development was instantaneous and the absorbance remained unchanged even after 24 h of mixing when kept in the dark. Linear calibration graphs (0-5 x 10/sup -5/M sulfite ions) were obtained at optimal reaction conditions of 7 x 10/sup -5/M TNP-amino acid and pH 8.0 phosphate buffer (0.05 M). The investigation of the effect of several diverse ions revealed an interference by sulfide and mercury ions at concentration levels of 10/sup -4/M. The standard deviation of determining 3 x 10/sup -5/M sulfite solution (10 times) was 1.474 x 10/sup -7/M. 22 references, 2 figures, 1 table.

Al-Hajjaji, M.A.

1984-01-01

43

Phylogeography of Sulfate-Reducing Bacteria among Disturbed Sediments, Disclosed by Analysis of the Dissimilatory Sulfite Reductase Genes (dsrAB)  

PubMed Central

Sediment samples were collected worldwide from 16 locations on four continents (in New York, California, New Jersey, Virginia, Puerto Rico, Venezuela, Italy, Latvia, and South Korea) to assess the extent of the diversity and the distribution patterns of sulfate-reducing bacteria (SRB) in contaminated sediments. The SRB communities were examined by terminal restriction fragment (TRF) length polymorphism (TRFLP) analysis of the dissimilatory sulfite reductase genes (dsrAB) with NdeII digests. The fingerprints of dsrAB genes contained a total of 369 fluorescent TRFs, of which <20% were present in the GenBank database. The global sulfidogenic communities appeared to be significantly different among the anthropogenically impacted (petroleum-contaminated) sites, but nearly all were less diverse than pristine habitats, such as mangroves. A global SRB indicator species of petroleum pollution was not identified. However, several dsrAB gene sequences corresponding to hydrocarbon-degrading isolates or consortium members were detected in geographically widely separated polluted sites. Finally, a cluster analysis of the TRFLP fingerprints indicated that many SRB microbial communities were most similar on the basis of close geographic proximity (tens of kilometers). Yet, on larger scales (hundreds to thousands of kilometers) SRB communities could cluster with geographically widely separated sites and not necessarily with the site with the closest proximity. These data demonstrate that SRB populations do not adhere to a biogeographic distribution pattern similar to that of larger eukaryotic organisms, with the greatest species diversity radiating from the Indo-Pacific region. Rather, a patchy SRB distribution is encountered, implying an initially uniform SRB community that has differentiated over time. PMID:15691959

Perez-Jimenez, J. R.; Kerkhof, L. J.

2005-01-01

44

Dominant conformation of valsartan in sodium dodecyl sulfate micelle environment.  

PubMed

The interaction of valsartan (VST), a novel antihypertensive drug, with sodium dodecyl sulfate (SDS) micelles has been investigated using Nuclear Magnetic Resonance (NMR) spectroscopy and Molecular Dynamics (MD) simulation. VST has two conformations in solution, exchanging slowly on the NMR time scale via the trans/cis (conformer A/B) isomerization of the amide bond. It is suggested that drugs in the sartan class incorporate and diffuse into biological membranes before they interact with AT(1) receptors. SDS is used to mimic the membrane environment to characterize two VST conformers. (1)H NMR chemical shift analysis, proton relaxation rates, and self-diffusion coefficient measurements suggest that conformer A has a higher binding affinity to SDS and is the dominant conformer distributed in the SDS micelles. The location of VST in the micelles is determined by NOE measurements and by the MD simulation, showing that the butyl chain and biphenyl groups of VST interact with the alkyl group of SDS through hydrophobic interactions. Preferable binding free energy is found for conformer A by the MD simulation, which demonstrates that the relatively concentrated hydrophobic surface of conformer A is responsible for its higher affinity to the micelles. Our results are in good agreement with a recent simulation of VST bound onto the AT(1) receptor by Potamitis et. al (J. Chem. Inf. Model. 2009) who demonstrate that conformer A (trans conformation in their definition) is the one binding to the receptor. The results presented in our study suggest that the biological membrane plays an essential role in stabilization of the active state of VST. Thus, understanding the interactions between the sartan drugs and the membrane environment should facilitate the studies of the functional mechanism of these compounds with their receptor and provide insight on the development of new approaches for drug discovery. PMID:20131883

Li, Fang; Wang, Lingyun; Xiao, Nan; Yang, Minghui; Jiang, Ling; Liu, Maili

2010-03-01

45

Inactivation of prions by acidic sodium dodecyl sulfate.  

PubMed

Prompted by the discovery that prions become protease-sensitive after exposure to branched polyamine dendrimers in acetic acid (AcOH) (S. Supattapone, H. Wille, L. Uyechi, J. Safar, P. Tremblay, F. C. Szoka, F. E. Cohen, S. B. Prusiner, and M. R. Scott, J. Virol. 75:3453-3461, 2001), we investigated the inactivation of prions by sodium dodecyl sulfate (SDS) in weak acid. As judged by sensitivity to proteolytic digestion, the disease-causing prion protein (PrPSc) was denatured at room temperature by SDS at pH values of < or =4.5 or > or =10. Exposure of Sc237 prions in Syrian hamster brain homogenates to 1% SDS and 0.5% AcOH at room temperature resulted in a reduction of prion titer by a factor of ca. 10(7); however, all of the bioassay hamsters eventually developed prion disease. When various concentrations of SDS and AcOH were tested, the duration and temperature of exposure acted synergistically to inactivate both hamster Sc237 prions and human sporadic Creutzfeldt-Jakob disease (sCJD) prions. The inactivation of prions in brain homogenates and those bound to stainless steel wires was evaluated by using bioassays in transgenic mice. sCJD prions were more than 100,000 times more resistant to inactivation than Sc237 prions, demonstrating that inactivation procedures validated on rodent prions cannot be extrapolated to inactivation of human prions. Some procedures that significantly reduced prion titers in brain homogenates had a limited effect on prions bound to the surface of stainless steel wires. Using acidic SDS combined with autoclaving for 15 min, human sCJD prions bound to stainless steel wires were eliminated. Our findings form the basis for a noncorrosive system that is suitable for inactivating prions on surgical instruments, as well as on other medical and dental equipment. PMID:16352557

Peretz, David; Supattapone, Surachai; Giles, Kurt; Vergara, Julie; Freyman, Yevgeniy; Lessard, Pierre; Safar, Jiri G; Glidden, David V; McCulloch, Charles; Nguyen, Hoang-Oanh B; Scott, Michael; Dearmond, Stephen J; Prusiner, Stanley B

2006-01-01

46

Molten lithium sulfate-sodium sulfate-potassium sulfate eutectic: oxidation-reduction reactions of transition-metal compounds  

SciTech Connect

Sulfur dioxide was found to reduce a number of first-row transition-metal compounds in molten ternary sulfate eutectic, the ease of reduction being Cr(VI) > Mn(IV) > Fe(III) > Cu(II). A number of other, probably polymeric, cations (Ti(IV), Nb(V), Mo(VI), Ta(V), W(VI)) were not reduced. Potassium dichromate was unstable, slowly decomposing to chromium(III) oxide, chromate, and oxygen, and was converted to chromate by solutions of sodium carbonate. Chromium metal was little attacked by the ternary eutectic, but copper metal reduced copper(II) to copper(I) cations. Solutions of potassium pyrosulfate decomposed thermally but also oxidized chromium metal (to Cr(III)) and iron(II) (to Fe(III)) and reduced manganese(IV) oxide (to Mn(II)) and chromium(VI) (completely to chromium(III)). Though simple cations (Fe(II), Mn(II)) accelerated the thermal decomposition of pyrosulfate, the more polymeric cations (Ti(IV), Nb(V), Mo(VI), Ta(V), W(VI)) caused considerably less evolution of sulfur trioxide. 25 references, 4 figures, 3 tables.

Dearnaley, R.I.; Kerridge, D.H.; Rogers, D.J.

1986-05-07

47

Manipulation and characterization of aqueous sodium dodecyl sulfate/sodium chloride aerosol particles.  

PubMed

Aerosol optical tweezers coupled with Raman spectroscopy can allow the detailed investigation of aerosol dynamics. We describe here measurements of the evolving size, composition, and phase of single aqueous aerosol droplets containing the surfactant sodium dodecyl sulfate and the inorganic salt sodium chloride. Not only can the evolving wet particle size be probed with nanometer accuracy, but we show that the transition to a metastable microgel particle can be followed, demonstrating that optical tweezers can be used to manipulate both spherical and non-spherical aerosol particles. Further, through the simultaneous manipulation and characterization of two aerosol droplets of different composition in two parallel optical traps, the phase behavior of a surfactant-doped particle and a surfactant-free droplet can be compared directly in situ. We also illustrate that the manipulation of two microgel particles can allow studies of the coagulation and interaction of two solid particles. Finally, we demonstrate that such parallel measurements can permit highly accurate comparative measurements of the evolving wet particle size of a surfactant-doped droplet with a surfactant-free droplet. PMID:18044858

Buajarern, Jariya; Mitchem, Laura; Reid, Jonathan P

2007-12-20

48

Molecular Dynamics Simulation of Sodium Dodecyl Sulfate Micelle in Water: Micellar Structural Characteristics and Counterion Distribution  

E-print Network

Molecular Dynamics Simulation of Sodium Dodecyl Sulfate Micelle in Water: Micellar Structural An all-atom 5 nanosecond molecular dynamics simulation of a water-solvated micelle containing 60 sodium, and the orientation of the monomers toward the micelle center of mass were evaluated. The results indicate a stable

Perera, Lalith

49

Chitosan and sodium sulfate as excipients in the preparation of prolonged release theophylline tablets.  

PubMed

The major objectives of this study were to monitor the effect of cross-linking of cationic chitosan in acidic media with sulfate anion during granules preparation by wet granulation method prior to tableting using theophylline (TPH) as a model drug. The prepared granules and the compressed tablets were subjected to in vitro evaluation. The properties of the prepared matrix granules and the compressed tablets were dependent on chitosan:sodium sulfate weight ratios, chitosan content, and molecular weight of chitosan. The prepared granules of all batches showed excellent to passable flowability and were suitable for compression into tablets. Most of the granules were hard and expected to withstand handling during the subsequent compression into tablets. Granules with high friabilities were only those prepared with a high amount of sodium sulfate or low amount of chitosan. Compression of granule batches yield nondisintegrating tablets that showed a decrease in tensile strength with the increase of sodium sulfate content at high chitosan:sodium sulfate weight ratio or with decrease of chitosan content. On the other hand, friability of tablets was increased in the presence of an excessive amount of sodium sulfate and low chitosan content as observed with granules. Slow TPH release from the formulated tablets was achieved at 1:0.5 and 1:1 chitosan:sodium sulfate weight ratios where all or most of the cationic chitosan and sulfate anions were used in a cross-linking reaction during wet granulation. Ratios of 1:2 and 1:3 showed fast drug release, which support the hypothesis that excessive unreacted water-soluble sodium sulfate might increase the porosity of the nondesintegrating tablets during dissolution. Slow drug release was also obtained with high molecular weight chitosan, whereas changing the hardness of the tablets did not significantly change the release profile of the drug as long as the tablets are intact during dissolution. Furthermore, slow drug release was observed as the total amount of chitosan was increased in the formulated tablets. A comparative in vivo study between the chosen formulated tablets (1:1 chitosan:sodium sulfate ratio that contains 10% high molecular weight chitosan) and the commercial Quibron tablets indicated prolonged appearance of the drug in dogs' plasma for both formulations with no significant differences (p > 0.05) in rate and extent of drug absorption. The formulated tablets showed 103.16% bioavailability relative to that of the commercial tablets. PMID:16093204

Alsarra, Ibrahim A; El-Bagory, Ibrahim; Bayomi, Mohsen A

2005-05-01

50

Chlorine Absorption in Sulfite Solutions  

Microsoft Academic Search

The rate of chlorine (5 to 300 ppm Cl2) absorption into aqueous sulfite\\/bisulfite (0 to 10 mM S(IV)) was measured using a stirred?cell reactor and a wetted?wall column at pH 4.7 and 5.7. Chlorine absorption was modeled using the theory of mass transfer with fast reaction. Chlorine reacts quickly with S(IV) to form chloride and sulfate near the gas\\/liquid interface. The rate

Sharmistha Roy; Gary T. Rochelle

2004-01-01

51

Hydrophobic interactions between polymethacrylic acid and sodium laureth sulfate in aqueous solutions  

NASA Astrophysics Data System (ADS)

The role of hydrophobic interaction in the development of associative processes is demonstrated, based on the concentration dependences of the viscosity and pH of binary solutions of polymethacrylic acid as an anionic polyelectrolyte and sodium laureth sulfate as an anionic surfactant. It is found that the inflection point on the dependence of the difference between the pH values of binary solutions of polymethacrylic acid and sodium laureth sulfate on the polyelectrolyte concentration is a criterion for determining the predominant contribution from hydrophobic interaction, as is the inflection point on the dependence of pH of individual solutions of polymethacrylic acid on the polyelectrolyte concentration.

Yaremko, Z. M.; Fedushinskaya, L. B.; Burka, O. A.; Soltys, M. N.

2014-09-01

52

Determination of free sulfites (SO3-2) in dried fruits processed with sulfur dioxide by ion chromatography through anion exchange column and conductivity detection.  

PubMed

A simple and effective anion ion chromatography (IC) method with anion exchange column and conductivity detector has been developed to determine free sulfites (SO3-2) in dried fruits processed with sulfur dioxide. No oxidation agent, such as hydrogen peroxide, is used to convert sulfites to sulfates for IC analysis. In addition, no stabilizing agent, such as formaldehyde, fructose or EDTA, is required during the sample extraction. This method uses aqueous 0.2 N NaOH as the solvent for standard preparation and sample extraction. The sulfites, either prepared from standard sodium sulfite powder or extracted from food samples, are presumed to be unbound SO3-2 in aqueous 0.2 N NaOH (pH > 13), because the bound sulfites in the sample matrix are released at pH > 10. In this study, sulfites in the standard solutions were stable at room temperature (i.e., 15-25 degrees C) for up to 12 days. The lowest standard of the linear calibration curve is set at 1.59 microg/mL SO3-2 (equivalent to 6.36 microg/g sample with no dilution) for analysis of processed dried fruits that would contain high levels (>1000 microg/g) of sulfites. As a consequence, this method typically requires significant dilution of the sample extract. Samples are prepared with a simple procedure of sample compositing, extraction with aqueous 0.2 N NaOH, centrifugation, dilution as needed, and filtration prior to IC. The sulfites in these sample extracts are stable at room temperature for up to 20 h. Using anion IC, the sulfites are eluted under isocratic conditions with 10 mM aqueous sodium carbonate solution as the mobile phase passing through an anion exchange column. The sulfites are easily separated, with an analysis run time of 18 min, regardless of the dried fruit matrix. Recoveries from samples spiked with sodium sulfites were demonstrated to be between 81 and 105% for five different fruit matrixes (apricot, golden grape, white peach, fig, and mango). Overall, this method is simple to perform and effective for the determination of high levels of sulfites in dried fruits. PMID:24282955

Liao, Benjamin S; Sram, Jacqueline C; Files, Darin J

2013-01-01

53

Structure-Based Alteration of Substrate Specificity and Catalytic Activity of Sulfite Oxidase from Sulfite Oxidation to Nitrate Reduction  

SciTech Connect

Eukaryotic sulfite oxidase is a dimeric protein that contains the molybdenum cofactor and catalyzes the metabolically essential conversion of sulfite to sulfate as the terminal step in the metabolism of cysteine and methionine. Nitrate reductase is an evolutionarily related molybdoprotein in lower organisms that is essential for growth on nitrate. In this study, we describe human and chicken sulfite oxidase variants in which the active site has been modified to alter substrate specificity and activity from sulfite oxidation to nitrate reduction. On the basis of sequence alignments and the known crystal structure of chicken sulfite oxidase, two residues are conserved in nitrate reductases that align with residues in the active site of sulfite oxidase. On the basis of the crystal structure of yeast nitrate reductase, both positions were mutated in human sulfite oxidase and chicken sulfite oxidase. The resulting double-mutant variants demonstrated a marked decrease in sulfite oxidase activity but gained nitrate reductase activity. An additional methionine residue in the active site was proposed to be important in nitrate catalysis, and therefore, the triple variant was also produced. The nitrate reducing ability of the human sulfite oxidase triple mutant was nearly 3-fold greater than that of the double mutant. To obtain detailed structural data for the active site of these variants, we introduced the analogous mutations into chicken sulfite oxidase to perform crystallographic analysis. The crystal structures of the Mo domains of the double and triple mutants were determined to 2.4 and 2.1 {angstrom} resolution, respectively.

Qiu, James A.; Wilson, Heather L.; Rajagopalan, K.V. (Duke)

2012-04-18

54

How Does Sodium Lauryl Sulfate Alter the Skin Barrier Function in Man? A Multiparametric Approach  

Microsoft Academic Search

The effects of topically applied sodium lauryl sulfate were studied in vivo, in man, through noninvasive methods and compared with those obtained in vitro, using human stratum corneum as a model. The results show that the very marked increase of transepidermal water loss obtained in vivo cannot be related to any removal of epidermal lipids. The most likely explanation of

J. L. Lévêque; J. de Rigal; D. Saint-Léger; D. Billy

1993-01-01

55

Adsorption of Sodium Dodecyl Sulfate on Functionalized Graphene Measured by Conductometric Titration  

E-print Network

sheets (FGSs), which can be produced in large quantities by thermal exfoliation and reduction of graphite" of surface micelles. Compared to the basal plane of graphite (i.e., pristine graphene), in which carbon atomsAdsorption of Sodium Dodecyl Sulfate on Functionalized Graphene Measured by Conductometric

Aksay, Ilhan A.

56

DETERMINATION OF SURFACTANT SODIUM LAURYL ESTHER SULFATE BY ION PAIRING CHROMATOGRAPHY WITH SUPPRESED CONDUCTIVITY DETECTION  

EPA Science Inventory

A method for the determination of the anionic Steol CS-330 surfactant is described. S-330 is a complex mixture of oligomers due to the various sizes of fatty alcohols and the number of moles of the ethoxylation. he main component of CS-330 is sodium lauryl ether sulfate (SLES). i...

57

DETERMINATION OF SURFACTANT SODIUM LAURYL ETHER SULFATE BY ION PAIRING CHROMATOGRAPHY WITH SUPPRESSED CONDUCTIVITY DETECTION  

EPA Science Inventory

A method for the determination of the anionic Steol CS-330 surfactant is described. CS-330 is a complex mixture of oligomers due to the various sizes of fatty alcohols and the number of moles of the ethoxylation. The main component of CS-330 is sodium lauryl ether sulfate (SLES)....

58

Effect of eutectic lithium sulfate-sodium sulfate flux on the synthesis of lead magnesium niobate  

Microsoft Academic Search

The effect of the amount of sulfate flux (Li2SO4-Na2SO4) on the phase stability and dielectric properties of lead magnesium niobate ceramics prepared by molten salt synthesis, has been studied as a function of calcining and sintering temperatures. The percentage of perovskite phase tended to increase with increasing the amount of flux and calcination temperature. When powders containing the same amount

K. H. Yoon; Y. S. Cho; D. H. Kang; K. Uchino; K. Y. Oh

1994-01-01

59

The hydration of interstitial Portland cement phases in sodium hydroxide and magnesium sulfate solutions  

NASA Astrophysics Data System (ADS)

Formation of sulfoaluminate compounds was investigated by isothermal calorimetry and X-ray diffraction (XRD). Tricalcium aluminate/gypsum mixtures with a molar ratio of 1:1 sulfate-to-aluminate were hydrated at constant temperatures from 30 to 90°C; in de-ionized water, in 200mM and in 500mM sodium hydroxide (NaOH) solutions. Hydration in de-ionized water produced ettringite and monosulfate as the dominant crystalline phases, regardless of temperature. Complex assemblages of phases formed in 200mM and 500mM sodium hydroxide including ettringite, monosulfate and U-phase, at all temperatures. Hydration of monosulfate and gypsum was also carried out at constant temperatures from 30° to 80°C using de-ionized water and 0.2M, 0.5M, and 1.0M sodium hydroxide (NaOH) solutions. Ettringite was found to be the dominant crystalline phase over the entire temperature range and at all sodium hydroxide concentrations. A sodium-substituted monosulfate phase was formed as a hydration product in the 1.0M sodium hydroxide solution regardless of temperature. Sulfoaluminate compounds formed by tricalcium aluminate hydration in magnesium sulfate solution were investigated by isothermal calorimetry, XRD, and scanning electron microscopy (SEM). Hydration was carried out in 0.5, 1.0 and 3.0M magnesium sulfate solutions and isothermally at temperatures from 30 to 80°C. Monosulfate, ettringite, gypsum and a hydrogarnet phase (Ca3Al2O6·6H2O) were all observed as hydration products. Monosulfate and hydrogarnet were the only phases observed for hydration in 0.5 and 1.0M magnesium sulfate solutions. Ettringite was the dominant crystalline phase after hydration in 3.0M solution, regardless of temperature. To investigate the rate of hydration, reactions at 60°C in 3.0M magnesium sulfate solution were quenched after 26 minutes, 73 minutes, 2.5 hours and 12 hours to establish the evolution of hydrated phases. Depending on hydration times ettringite, monosulfate, gypsum, hydrogarnet and residual tricalcium aluminate were observed. No crystalline magnesium-rich phases were detected by XRD. The products formed by hydration of tetracalcium aluminoferrite (Ca 2AlFeO5) and magnesium sulfate solutions were investigated by isothermal calorimetry, XRD and SEM analyses. Hydration reactions were carried out isothermally at temperatures from 25 to 80°C in 0.25M, 0.5M, 1.0M, 2.0M, and 3.0M magnesium sulfate solutions. Gypsum was the initial hydration product in all magnesium sulfate concentrations and was the only crystalline hydration product in 2.0M and 3.0M magnesium sulfate solutions. Monosulfate was the dominant crystalline phase produced over the entire temperature range when hydration was carried out in magnesium sulfate concentrations between 0.25M and 1.0M. No crystalline phases incorporating iron were observed regardless of magnesium sulfate concentration or temperature. Hydration in 1.0M MgSO 4 solution was more extensively investigated at 50°C. SEM observations indicated gypsum formed initially, consisting of fine particles (<5 mum). Complex phase assemblages including gypsum, ettringite, and monosulfate were present at intermediate times. Monosulfate was the final crystalline hydration product. Amorphous solids produced include a calcium/iron-rich gel and a magnesium/aluminum/sulfate-rich phase. The calcium/iron-rich gel is the only iron-rich phase observed in the hydrated phase assemblage.

Clark, Boyd Arthur

60

Effect of sodium sulfate on the gelling behavior of agarose and water structure inside gel networks.  

PubMed

Agarose hydrogels which constitute a special class of soft matter are undoubtedly one of the most studied biopolymer gels. However, certain issues such as why the sulfate salts and sulfate content in the agarose molecules reduce the gel strength are still not very clear. The present work provides a detailed analysis of structural changes with respect to coil-helix transition or aggregation of helices in the aqueous agarose solutions and hydrogels that accompanied the systematic addition of sodium sulfate. A combined approach which includes the differential scanning calorimetry and temperature-dependent vacuum-ultraviolet circular dichroism measurements permitted the accurate estimates of the energy changes for coil-helix transition and helix-helix interactions. The hydration process of agarose molecule investigated from differential scanning calorimetry and concentration-dependent ultrasonic measurements indicated the loss of both the freeze bound and nonfreezable water molecules with the increase of sulfate content in the solution. Temperature-dependent fluorescence measurements using pyrene as a probe indicated polarity changes when the gel network is created in waters of different salt concentration. Changes in the hydrogen bonding of the water molecules confined in the gel network have been monitored from the intensity ratios of ice-like and liquid-like -OH stretching band of water Fourier transform infrared (FTIR) spectra. Analysis of the -OH stretching band showed the strengthening of hydrogen bonding of water molecules in the gel which tend to weaken with the subsequent addition of sodium sulfate. PMID:19193039

Singh, Tejwant; Meena, Ramavtar; Kumar, Arvind

2009-02-26

61

Effect of potassium sodium tartrate and sodium citrate on the preparation of -calcium sulfate hemihydrate from flue gas desulfurization gypsum in a concentrated electrolyte solution  

Microsoft Academic Search

Flue gas desulfurization (FGD) gypsum mainly composed of calcium sulfate dihydrate (DH) was used as a raw material to obtain alpha-calcium sulfate hemihydrate (-HH) through dehydration in a Ca-Mg-K-Cl-solution medium at 95{sup o}C under atmospheric pressure. The effects of potassium sodium tartrate and sodium citrate on the preparation of alpha-HH in the electrolyte solution were investigated. The results revealed that

Zhuoxian Shen; Baohong Guan; Hailu Fu; Liuchun Yang

2009-01-01

62

ETTRINGITE FORMATION IN LOW C 3A PORTLAND CEMENT EXPOSED TO SODIUM SULFATE SOLUTION  

Microsoft Academic Search

Four low-C3A Portland cements with different C3S content (40 to 74%) were stored for two years in sodium sulfate solution. Expansion and flexural strength were monitored as mechanical properties, while the microstructural changes were studied by X-ray diffraction and scanning electron microscopy using X-ray microanalysis. For this cement type, the alteration processes can be described by three stages: induction, gypsum

M. A. González; E. F. Irassar

1997-01-01

63

Phase diagrams of water and sodium dodecyl sulfate combined with four commercial nonionic surfactants  

Microsoft Academic Search

Phase diagrams in which water was combined with sodium dodecyl sulfate, plus one of four nonionic surfactants, as well as\\u000a an aliphatic oil, were determined by visual observation and low-angle X-ray diffractometry. The results agreed with earlier\\u000a investigations on specially synthesized polyethyleneglycol alkyl ether surfactants, except that the extended water-in-oil\\u000a microemulsion areas were not found with the commercial surfactants.

S. E. Friberg; M. Chiu

1992-01-01

64

Structural transformations in a water- n -octane + chloroform-sodium dodecyl sulfate- n -pentanol microemulsion  

Microsoft Academic Search

Conductivity, viscosity, and water and oil solubilization are measured, and the parameter of hydrophilic-lipophilic balance\\u000a is calculated for stable water-n-octane + chloroform-n-pentanol-sodium dodecyl sulfate microemulsions (Winsor Type IV system) at a water content of 2.5–56 vol %. Domains of the\\u000a most probable existence of globular and bicontinuous structures and the boundaries of the transitions between the following\\u000a states of the

A. V. Sineva; D. S. Ermolat’ev; A. V. Pertsov

2007-01-01

65

Effect of Interfacial Alcohol Concentrations on Oil Solubilization by Sodium Dodecyl Sulfate Micelles  

Microsoft Academic Search

Alcohol partitioning and its effect on oil solubilization in Winsor Type I microemulsion systems was investigated. The microemulsion systems consisted of sodium dodecyl sulfate (SDS), pentanol, isopropanol (IPA), and dodecane, with either deionized water or an aqueous solution of 50 mM CaCl2. Alcohol partitioning between aqueous, oil, and interfacial phases of the microemulsion was described using a pseudophase model in

Meifang Zhou; R. Dean Rhue

2000-01-01

66

Solubility of hydrogen sulfide in aqueous solutions of the single salts sodium sulfate, ammonium sulfate, sodium chloride, and ammonium chloride at temperatures from 313 to 393 K and total pressures up to 10 MPa  

SciTech Connect

New experimental results for the solubility of hydrogen sulfide in aqueous solutions of the single salts sodium sulfate, ammonium sulfate, sodium chloride, and ammonium chloride at temperatures from 313 to 393 K and total pressures up to 10 MPa are reported. As in the salt-free system, a second-hydrogen sulfide-rich--liquid phase is observed at high hydrogen sulfide concentrations. A model to describe the phase equilibrium is presented. Calculations are compared to the new experimental data.

Xia, J.; Kamps, A.P.S.; Rumpf, B.; Maurer, G.

2000-04-01

67

Interactions between selected bile salts and Triton X-100 or sodium lauryl ether sulfate  

PubMed Central

Background In order to develop colloidal drug carriers with desired properties, it is important to determine physico-chemical characteristics of these systems. Bile salt mixed micelles are extensively studied as novel drug delivery systems. The objective of the present investigation is to develop and characterize mixed micelles of nonionic (Triton X-100) or anionic (sodium lauryl ether sulfate) surfactant having oxyethylene groups in the polar head and following bile salts: cholate, deoxycholate and 7-oxodeoxycholate. Results The micellization behaviour of binary anionic-nonionic and anionic-anionic surfactant mixtures was investigated by conductivity and surface tension measurements. The results of the study have been analyzed using Clint's, Rubingh's, and Motomura's theories for mixed binary systems. The negative values of the interaction parameter indicate synergism between micelle building units. It was noticed that Triton X-100 and sodium lauryl ether sulfate generate the weakest synergistic interactions with sodium deoxycholate, while 7-oxodeoxycholate creates the strongest attractive interaction with investigated co-surfactants. Conclusion It was concluded that increased synergistic interactions can be attributed to the larger number of hydrophilic groups at ? side of the bile salts. Additionally, 7-oxo group of 7-oxodeoxycholate enhance attractive interactions with selected co-surfactants more than 7-hydroxyl group of sodium cholate. PMID:22206681

2011-01-01

68

Hydrothermal synthesis of sodium tungstate nanorods and nanobundles in the presence of sodium sulfate  

SciTech Connect

Sodium tungstate nanorods and nanobundles have been successfully prepared, for the first time, through a simple salt-assisted hydrothermal route based on the reaction between Na{sub 2}WO{sub 4} and HCl in aqueous solution. The resultant sodium tungstate nanorods and nanobundles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and selected area electronic diffraction (SAED) techniques. The ingredients of the sample have been detected by energy-dispersive spectrum (EDS) method. It is found that hydrothermal temperature and time play important roles in the control of the morphology and size of the products.

Cao Guangxiang [Department of Chemistry and Chemical Engineering, Shandong University, 27 Shanda South Road, Jinan 250100 (China); Song Xinyu [Department of Chemistry and Chemical Engineering, Shandong University, 27 Shanda South Road, Jinan 250100 (China); Yu Haiyun [Department of Chemistry and Chemical Engineering, Shandong University, 27 Shanda South Road, Jinan 250100 (China); Fan Chunhua [Department of Chemistry and Chemical Engineering, Shandong University, 27 Shanda South Road, Jinan 250100 (China); Yin Zhilei [Department of Chemistry and Chemical Engineering, Shandong University, 27 Shanda South Road, Jinan 250100 (China); Sun Sixiu [Department of Chemistry and Chemical Engineering, Shandong University, 27 Shanda South Road, Jinan 250100 (China)]. E-mail: ssx@sdu.edu.cn

2006-02-02

69

Ab Initio Study of Thermodynamic Properties of Lithium, Sodium, and Potassium Sulfates  

NASA Astrophysics Data System (ADS)

The thermodynamic parameters of lithium, sodium, and potassium single and double sulfate crystals are determined by the method of ab initio calculation of a linear combination of atomic orbitals in the gradient approximation of density functional theory using the software package CRYSTAL09 within the framework of the quasi-harmonic approximation of the Debye theory. It is demonstrated that the standard entropies and heat capacities as well as the temperature dependences are in satisfactory agreement with the available experimental data. The average frequency, Debye temperature, and thermal conductivity coefficient increase with external pressure, whereas the Gruneisen parameter decreases. The dependences of the potentials of free and internal energies on the temperature and volume are expressed through the Birch-Murnaghan equation of state and a square-law dependence on these parameters of their vibrational components. The thermodynamic parameters of lithium-potassium sulfate appear closer to potassium sulfate, whereas for sodium-potassium, they lie between the corresponding parameters for single compounds.

Zhuravlev, Yu. N.; Bugaeva, I. A.; Zhuravleva, L. V.

2013-11-01

70

Synthesis and surface properties of chemodegradable anionic surfactants: Sodium (2- n -alkyl-1,3-dioxan-5-yl)sulfates  

Microsoft Academic Search

In the reaction of cis- and trans-2-n-alky-5-hydroxyl-1,3-dioxane mixtures with SO3 pyridine complex, followed by neutralization with sodium hydroxide or sodium carbonate, a new group of anionic surfactants,\\u000a i.e., sodium cis- and trans-(2-n-alkyl-1,3-dioxan-5-yl)sulfates were obtained. The hydrophobic intermediates used in the sulfation reaction were obtained\\u000a in high yields from four-component glycerol acetals by the process of transacetalization and selective crystallization of

Andrzej Piasecki; Adam Soko?owski; Bogdan Burczyk; Urszula Kotlewska

1997-01-01

71

Analysis of Furaneol in tomato using dynamic headspace sampling with sodium sulfate.  

PubMed

High-flow dynamic headspace sampling with excess anhydrous sodium sulfate was found to be an effective method of isolating Furaneol from fresh tomatoes. Quantitative analysis was carried out by gas chromatography using maltol as internal standard. Furaneol was found in the highest concentrations (660-1100 ppb) in the summer crop of home-grown tomatoes and in some of the greenhouse hydroponically grown tomatoes, which are ripened on the plant before being transported to the supermarkets. Furaneol was found in the lowest concentrations (38-180 ppb) in the common ethylene-ripened, field-grown, supermarket tomatoes. PMID:11559136

Buttery, R G; Takeoka, G R; Naim, M; Rabinowitch, H; Nam, Y

2001-09-01

72

Chromium(VI) oxidation of alkanol components of sodium dodecyl sulfate reverse micelles  

SciTech Connect

Oxidation with potassium dichromate in perchloric acid medium of the alkanols 1-butanol, 1-hexanol, and 1-octanol, components of sodium dodecyl sulfate reverse micelles in alkanols, has been studied. The reaction rate is first-order with respect to Cr(VI) and depends linearly on the HClO{sub 4} concentration in the aqueous phase, but the reaction rate decreases with the amount of alcohol in the reverse micelles. To explain the kinetic results it is necessary to consider the intermicellar exchange of the reactants, which could depend on the thickness of the layer where the surfactant and the alcohol are located.

Rodenas, E.; Perez-Benito, E. (Univ. de Alcala de Henares, Madrid (Spain))

1991-11-14

73

Oxidation kinetics of by-product calcium sulfite  

E-print Network

. It is easier to dewater calcium sulfate wastes. Gypsum is pumped to the disposal area in the slurry form and settles by gravity. It can be stacked and stored in smaller volumes than that required for calcium sulfite sludge. A relatively uncontaminated gypsum... on a predetermined range and a specific surface area based on the assumption that the particles are perfect spheres can be generated. 4. Chemical Analysis Iodometric titration was used to determine the concentration of sulfite in the slurry. Iodine...

Othman, Hasliza

2012-06-07

74

Dissolution and solubility behavior of fenofibrate in sodium lauryl sulfate solutions.  

PubMed

The solubility of fenofibrate in pH 6.8 McIlvaine buffers containing varying concentrations of sodium lauryl sulfate was determined. The dissolution behavior of fenofibrate was also examined in the same solutions with rotating disk experiments. It was observed that the enhancement in intrinsic dissolution rate was approximately 500-fold and the enhancement in solubility was approximately 2000-fold in a pH 6.8 buffer containing 2% (w/v) sodium lauryl sulfate compared to that in buffer alone. The micellar solubilization equilibrium coefficient (k*) was estimated from the solubility data and found to be 30884+/-213 L/mol. The diffusivity for the free solute, 7.15x10(-6) cm2/s, was calculated using Schroeder's additive molal volume estimates and Hayduk-Laurie correlation. The diffusivity of the drug-loaded micelle, estimated from the experimental solubility and dissolution data and the calculated value for free solute diffusivity, was 0.86x10(-6) cm2/s. Thus, the much lower enhancement in dissolution of fenofibrate compared to its enhancement in solubility in surfactant solutions appears to be consistent with the contribution to the total transport due to enhanced micellar solubilization as well as a large decrease (approximately 8-fold) in the diffusivity of the drug-loaded micelle. PMID:16306004

Granero, Gladys E; Ramachandran, Chandrasekharan; Amidon, Gordon L

2005-10-01

75

Theoretical and Experimental Studies of the Spin Trapping of Inorganic Radicals by 5,5-Dimethyl-1-Pyrroline N-Oxide (DMPO). 3. Sulfur Dioxide, Sulfite and Sulfate Radical Anions  

PubMed Central

Radical forms of sulfur dioxide (SO2), sulfite (SO32?), sulfate (SO42?), and their conjugate acids are known to be generated in vivo through various chemical and biochemical pathways. Oxides of sulfur are environmentally pervasive compounds and are associated with a number of health problems. There is growing evidence that their toxicity may be mediated by their radical forms. Electron paramagnetic resonance (EPR) spin trapping using the commonly used spin trap, 5,5-dimethyl-1-pyrroline N-oxide (DMPO), has been employed in the detection of SO3•? and SO4•?. The thermochemistries of SO2•?, SO3•?, SO4•?, and their respective conjugate acids addition to DMPO were predicted using density functional theory (DFT) at the PCM/B3LYP/6-31+G**//B3LYP/6-31G* level. No spin adduct was observed for SO2•? by EPR but an S-centered adduct was observed for SO3•? and an O-centered adduct for SO4•?. Determination of adducts as S- or O-centered was made via comparison based on qualitative trends of experimental hfcc’s with theoretically calculated ones. The thermodynamics of the non-radical addition of SO32? and HSO3? to DMPO followed by conversion to the corresponding radical adduct via the Forrester-Hepburn mechanism was also calculated. Adduct acidities and decomposition pathways were investigated as well, including an EPR experiment using H217O to determine the site of hydrolysis of O-centered adducts. The mode of radical addition to DMPO is predicted to be governed by several factors, including spin population density, and geometries stabilized by hydrogen bonds. The thermodynamic data supports evidence for the radical addition pathway over the nucleophilic addition mechanism. PMID:22668066

Zamora, Pedro L.; Villamena, Frederick A.

2012-01-01

76

Theoretical and experimental studies of the spin trapping of inorganic radicals by 5,5-dimethyl-1-pyrroline N-oxide (DMPO). 3. Sulfur dioxide, sulfite, and sulfate radical anions.  

PubMed

Radical forms of sulfur dioxide (SO(2)), sulfite (SO(3)(2-)), sulfate (SO(4)(2-)), and their conjugate acids are known to be generated in vivo through various chemical and biochemical pathways. Oxides of sulfur are environmentally pervasive compounds and are associated with a number of health problems. There is growing evidence that their toxicity may be mediated by their radical forms. Electron paramagnetic resonance (EPR) spin trapping using the commonly used spin trap, 5,5-dimethyl-1-pyrroline N-oxide (DMPO), has been employed in the detection of SO(3)(•-) and SO(4)(•-). The thermochemistries of SO(2)(•-), SO(3)(•-), SO(4)(•-), and their respective conjugate acids addition to DMPO were predicted using density functional theory (DFT) at the PCM/B3LYP/6-31+G**//B3LYP/6-31G* level. No spin adduct was observed for SO(2)(•-) by EPR, but an S-centered adduct was observed for SO(3)(•-)and an O-centered adduct for SO(4)(•-). Determination of adducts as S- or O-centered was made via comparison based on qualitative trends of experimental hfcc's with theoretical values. The thermodynamics of the nonradical addition of SO(3)(2-) and HSO(3)(-) to DMPO followed by conversion to the corresponding radical adduct via the Forrester-Hepburn mechanism was also calculated. Adduct acidities and decomposition pathways were investigated as well, including an EPR experiment using H(2)(17)O to determine the site of hydrolysis of O-centered adducts. The mode of radical addition to DMPO is predicted to be governed by several factors, including spin population density, and geometries stabilized by hydrogen bonds. The thermodynamic data supports evidence for the radical addition pathway over the nucleophilic addition mechanism. PMID:22668066

Zamora, Pedro L; Villamena, Frederick A

2012-07-01

77

Renaturation of enzymes after polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate  

SciTech Connect

A number of enzymes, including amylases, dehydrogenases, and proteases, were shown to be renaturable after polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. Enzyme activity was detected in situ by action on substrates introduced into the gel and subsequent staining of either the product or unreacted substrate. Enzymes appeared to recover activity as soon as the detergent diffused out of the gel. Renatured enzymes were retained in gels after electrophoresis longer than native enzymes which had been subjected to electrophoresis in the absence of detergent. Re-electrophoresis of the renatured enzymes showed that part of the retained activity was physically anchored to the gel, possibly by the folding of polypeptides around the gel matrix as the enzymes were renatured.

Lacks, S.A.; Springhorn, S.S.

1980-08-10

78

Phosphoprotein staining for sodium dodecyl sulfate-polyacrylamide gel electrophoresis using fluorescent reagent morin hydrate.  

PubMed

A fluorescence-based stain with 3,5,7,2',4'-pentahydroxyflavone (morin hydrate, MH) was designed to stain phosphoproteins in one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Al(3+) was applied as a "fixed bridge," providing an efficient energy transfer channel between phosphoprotein and MH, to produce a strong fluorescent complex for the determination of phosphoprotein. As little as 62.5ng of ?-casein (7 or 8 phosphates) and ?-casein (5 phosphates), 125ng of ovalbumin (2 phosphates), and ?-casein (1 phosphate) could be visualized with a wide linear dynamic range. In comparison with conventional methods, MH stain is a time-saving method that takes just 90min. It also has good compatibility with routine protein stainings such as Coomassie Brilliant Blue R (CBBR) and SYPRO Ruby for total protein analysis. PMID:23274386

Wang, Xu; Hwang, Sun-Young; Cong, Wei-Tao; Jin, Li-Tai; Choi, Jung-Kap

2013-04-01

79

Suppressive effect of berberine on experimental dextran sulfate sodium-induced colitis.  

PubMed

The anti-inflammatory effect of berberine was evaluated in murine model of acute experimental colitis induced by dextran sulfate sodium (DSS). Berberine, given orally at 40, 20, 10?mg/kg for 10 days, ameliorated all the supposed inflammatory symptoms of the induced colitis, such as body weightloss, blood hemoglobin reduction, high myeloperoxidase levels, and malondialdehyde content-inflamed mucosa. Furthermore, the cytokine production of splenic lymphocytes was analyzed. The results showed the IFN-? and IL-12 were increased, but IL-4 and IL-10 were decreased in DSS-induced colitis,when those were compared with the normal control. But the administration of berberine to DSS-induced colitis mice showed lower production of IFN-? and IL-12 and higher production of IL-4 and IL-10 than the DSS-induced colitis mice. The results suggest that the protective effects of berberine against the DSS-induced colitis may be associated with the regulation of cytokine production. PMID:22564173

Hong, Tie; Yang, Zhen; Lv, Chuan-Feng; Zhang, Yu

2012-06-01

80

Adsorption of sodium dodecyl sulfate on kaolin from different alcohol-water mixtures  

SciTech Connect

The adsorption of surfactants on solid/liquid interfaces is a subject of great interest especially for enhanced oil recovery processes. The adsorption of sodium dodecyl sulfate (SDS) onto kaolin from different alcohol-water mixtures has been studied. The alcohols used were 1-propanol, 1-butanol, 1-pentanol, and 1-decanol containing 3.5 or 7 wt% water. In all cases the adsorption isotherms show a rather steep rise at low surfactant concentrations. Thereafter, there is a more or less continuous leveling off. The plateau adsorption of SDS on kaolin is found to increase with increasing chain length of the alcohol in the alcohol-water solvent. The adsorption properties are discussed in relation to the dielectric constant of the solvents; the aggregation properties of the surfactant in the bulk phase and the molecular packing of the surfactant in the adsorbed state are also considered.

Blokhus, A.M.; Hoeiland, H.; Gjerde, M.I. [Univ. of Bergen (Norway). Dept. of Chemistry] [Univ. of Bergen (Norway). Dept. of Chemistry; Ersland, E.K. [Bergen Technological College (Norway)] [Bergen Technological College (Norway)

1996-05-10

81

Adsorption of Sodium Dodecyl Sulfate on Ge Substrate: The Effect of a Low-Polarity Solvent  

PubMed Central

This paper describes the adsorption of sodium dodecyl sulfate (SDS) molecules in a low polar solvent on Ge substrate by using Fourier transform infrared-attenuated total reflection (FTIR-ATR) spectroscopy and atomic force microscopy (AFM). The maximum SDS amount adsorbed is (5.0 ± 0.3) × 1014 molecules cm?2 in CHCl3, while with the use of CCl4 as subphase the ability of SDS adsorbed is 48% lower. AFM images show that depositions are highly disordered over the interface, and it was possible to establish that the size of the SDS deposition is around 30–40 nm over the Ge surface. A complete description of the infrared spectroscopic bands for the head and tail groups in the SDS molecule is also provided. PMID:22942685

Viana, Rommel B.; da Silva, Albérico B. F.; Pimentel, André S.

2012-01-01

82

Sodium Dodecyl Sulfate (SDS)-Loaded Nanoporous Polymer as Anti-Biofilm Surface Coating Material  

PubMed Central

Biofilms cause extensive damage to industrial settings. Thus, it is important to improve the existing techniques and develop new strategies to prevent bacterial biofilm formation. In the present study, we have prepared nanoporous polymer films from a self-assembled 1,2-polybutadiene-b-polydimethylsiloxane (1,2-PB-b-PDMS) block copolymer via chemical cross-linking of the 1,2-PB block followed by quantitative removal of the PDMS block. Sodium dodecyl sulfate (SDS) was loaded into the nanoporous 1,2-PB from aqueous solution. The SDS-loaded nanoporous polymer films were shown to block bacterial attachment in short-term (3 h) and significantly reduce biofilm formation in long-term (1 week) by gram-negative bacterium Escherichia coli. Tuning the thickness or surface morphology of the nanoporous polymer films allowed to extent the anti-biofilm capability. PMID:23377015

Li, Li; Molin, Soeren; Yang, Liang; Ndoni, Sokol

2013-01-01

83

The effect of medium chain length alcohols on the micellar properties of sodium dodecyl sulfate in sodium chloride solutions  

SciTech Connect

The effect of medium chain length alcohols on the micellar size and shape of sodium dodecyl sulfate in electrolyte solutions has been investigated by means of small angle neutron scattering (SANS), dynamic light scattering (DLS), and viscosity measurements. The surfactant content was kept constant throughout, at 0.04 m, and the alcohols used were 1-butanol, 1-pentanol, and 1-hexanol. The data from the various techniques are qualitatively in agreement. The SANS data generally fit a model for prolate ellipsoids with varying ratios of the major to minor axis. Addition of butanol first leads to a decrease in micellar size, the major to minor axis ratio decreases from about 6 to less than 2. However, as the butanol concentration exceeds 0.5 m, the micelles starts to grow again. The same can be seen from the diffusion coefficient as measured by DLS. Addition of pentanol or hexanol do not bring about this minimum in micellar size. The minor axis decreases and the major axis increases as these alcohols are added. Thus these alcohols make the prolate ellipsoidal micelles grow continuously towards large rod-like structures. The viscosity data are less detailed, but confirm the general trend upon alcohol addition.

Foerland, G.M.; Hoeiland, H. (Bergen Univ. (Norway). Dept. of Chemistry); Samseth, J. (Institute for Energy Technology, Kjeller (Norway)); Mortensen, K. (Risoe National Lab., Roskilde (Denmark))

1994-04-01

84

Cellulose extraction from orange peel using sulfite digestion reagents.  

PubMed

Orange peel (OP) was used as raw material for cellulose extraction. Two different pulping reagents were used, sodium sulfite and sodium metabisulfite. The effect of the main process parameters, sulfite agent dosage and reaction duration, on cellulose yield was investigated. A central composite rotatable design involving two variables at five levels and response surface methodology were used for the optimization of cellulose recovery. Other two invariable parameters were reaction temperature and hydromodulus. The optimum yields, referred to the weight of double extracted OP, were 40.4% and 45.2% for sodium sulfite and sodium metabisulfite digestions, respectively. The crude celluloses were bleached with hypochlorite and oxygen. The physicochemical characterization data of these cellulose materials indicate good levels of purity, low crystallinities, good whitenesses, good water retention and moderate molecular weights. According to these specific properties the recovered celluloses could be used as fillers, water absorbents, or as raw materials for cellulose derivatives. PMID:21893413

Bicu, Ioan; Mustata, Fanica

2011-11-01

85

Toxicity detection of sodium nitrite, borax and aluminum potassium sulfate using electrochemical method.  

PubMed

Based on the inhibition effect on the respiratory chain activity of microorganisms by toxicants, an electrochemical method has been developed to measure the current variation of a mediator in the presence of microorganisms contacted with a toxicant. Microelectrode arrays were adopted in this study, which can accelerate the mass transfer rate of an analyte to the electrode and also increase the total current signal, resulting in an improvement in detection sensitivity. We selected Escherichia coli as the testee and the standard glucose-glutamic acid as an exogenous material. Under oxygen restriction, the experiments in the presence of toxicant were performed at optimum conditions (solution pH 7.0, 37 degrees C and reaction for 3 hr). The resulting solution was then separated from the suspended microorganisms and was measured by an electrochemical method, using ferricyanide as a mediator. The current signal obtained represents the reoxidation of ferrocyanide, which was transformed to inhibiting efficiency, IC50, as a quantitative measure of toxicity. The IC50 values measured were 410, 570 and 830 mg/L for sodium nitrite, borax and aluminum potassium sulfate, respectively. The results show that the toxicity sequence for these three food additives is consistent with the value reported by other methods. Furthermore, the order of damage degree to the microorganism was also observed to be: sodium nitrite > borax > aluminum potassium sulfate > blank, according to the atomic force microscopy images of E. coli after being incubated for 3 hr with the toxic compound in buffer solutions. The electrochemical method is expected to be a sensitive and simple alternative to toxicity screening for chemical food additives. PMID:23923788

Yu, Dengbin; Yong, Daming; Dong, Shaojun

2013-04-01

86

Effect of Scutellariae Radix extract on experimental dextran-sulfate sodium-induced colitis in rats  

PubMed Central

AIM: To investigate the effect of Scutellariae Radix extract (SRE) on ulcerative colitis (UC) in rats induced by dextran-sulfate sodium (DSS). METHODS: Colitis was induced in male Sprague-Dawley (SD) rats (170-180 g) by 4% dextran sulfate sodium (DSS, wt/v; MW 54000) in drinking water for 8 d. The treated rats received 4% DSS and SRE orally (100 mg/kg per day). Control rats received either tap water or SRE only. Macroscopic assessment which included body weight changes, fecal occult blood and stool consistency were determined daily. At the appointed time, the rats were sacrificed and the entire colons were removed. The colon length and the myeloperoxidase (MPO) activity were measured. The severity of colitis was graded by morphological and histological assessments. The ion transport activity of the colonic mucosa was assessed by electrophysiological technique. RESULTS: Rats treated with oral administration of 4% DSS regularly developed clinical and macroscopic signs of colitis. Treatment with SRE relieved the symptoms, including the reduction in body weight, shortening and ulceration of the colon. Administration of SRE also significantly reduced the histological damage induced by DSS. Moreover, the ISC responses of the colonic mucosa to forskolin were suppressed after the induction of colitis. The stimulated ion transport activity of DSS-rats treated with SRE displayed significant improvement in the secretory responsiveness. CONCLUSION: SRE was effective in treating acute DSS-induced ulcerative colitis, as gauged by reduced clinical disease, improved macroscopic and histological damage scores, and enhanced recovery of normal colonic secretory function. PMID:17948935

Chung, Ho-Lam; Yue, Grace Gar-Lee; To, Ka-Fai; Su, Ya-Lun; Huang, Yu; Ko, Wing-Hung

2007-01-01

87

Surfactant-and Salt-Induced Growth of Normal Sodium Alkyl Sulfate Micelles Well above Their Critical Micelle Concentrations  

E-print Network

Surfactant- and Salt-Induced Growth of Normal Sodium Alkyl Sulfate Micelles Well above, dodecyl, and tetradecyl were studied. In all cases, the growth of the aggregates with added salt counterion concentration in the aqueous phase (supplied by the surfactant and the added salt). The constants

Bales, Barney

88

Thermoreversible Gel Formulations Containing Sodium Lauryl Sulfate or n-Lauroylsarcosine as Potential Topical Microbicides against Sexually Transmitted Diseases  

Microsoft Academic Search

The microbicidal efficacies of two anionic surfactants, sodium lauryl sulfate (SLS) and n-lauroylsarcosine (LS), were evaluated in cultured cells and in a murine model of herpes simplex type 2 (HSV-2) intravaginal infection. In vitro studies showed that SLS and LS were potent inhibitors of the infectivity of HSV-2 strain 333. The concentrations of SLS which inhibit viral infectivity by 50%

SYLVIE ROY; PIERRETTE GOURDE; JOCELYNE PIRET; A. Desormeaux; J. Lamontagne; C. Haineault; R. F. Omar; M. G. Bergeron

2001-01-01

89

Use of a Ferrous Sulfate - Sodium Dithionite Blend to Treat a Dissolved Phase Cr(VI) Plume  

EPA Science Inventory

A field study was conducted to evaluate the use of a combination of sodium dithionite and ferrous sulfate in creating an in situ redox zone for treatment of a dissolved phase Cr(VI) plume at a former industrial site. The reductant blend was injected into the path of a dissolved ...

90

Oxidation and characterization of FGD byproduct calcium sulfite and oxidized product  

E-print Network

and infrared spectroscopy. It was found to consist mainly of a solid solution of calcium sulfate and calcium sulfite hemihydrate, calcium sulfate dihydrate and unreacted calcium carbonate. 1 Pure CaSO3. ? H20 was synthesized as a model and was used.... Infrared Spectroscopy. X-ray Diffraction. . Scanning Electron Microscopy. . . . Particle Size Analysis. Measurement of Density. 23 24 25 25 25 26 Preparation of Calcium Sulfite Hemihydrate. . . . . . 27 TABLE OF CONTENTS (continued) CHAPTER...

Gupta, Anurag

2012-06-07

91

Effect of potassium sodium tartrate and sodium citrate on the preparation of {alpha}-calcium sulfate hemihydrate from flue gas desulfurization gypsum in a concentrated electrolyte solution  

SciTech Connect

Flue gas desulfurization (FGD) gypsum mainly composed of calcium sulfate dihydrate (DH) was used as a raw material to obtain alpha-calcium sulfate hemihydrate ({alpha}-HH) through dehydration in a Ca-Mg-K-Cl-solution medium at 95{sup o}C under atmospheric pressure. The effects of potassium sodium tartrate and sodium citrate on the preparation of alpha-HH in the electrolyte solution were investigated. The results revealed that the addition of potassium sodium tartrate (1.0 x 10{sup -2} - 2.5 x 10{sup -2}M) decreased the dehydration rate of FGD gypsum and increased the length/width (l/w) ratio of {alpha}-HH crystals, which could yield unfavorable strength properties. Addition of sodium citrate (1.0 x 10{sup -5} - 2.0 x 10{sup -5}M) slightly increased the dehydration rate of FGD gypsum and decreased the l/w ratio of {alpha}-HH crystals, which could be beneficial to increase strength. However, it also led to a partial formation of anhydrite (AH) crystals. AH was also the only dehydration product when the concentration of sodium citrate increased to 1.0 x 10{sup -4}M. Therefore, sodium citrate rather than potassium sodium tartrate could be used as an additive in Ca-Mg-K-Cl electrolyte solutions if alpha-HH with a shorter l/w ratio is the desired product from FGD gypsum dehydration. The concentration of sodium citrate should be properly controlled to reduce the formation of AH.

Shen, Z.X.; Guan, B.H.; Fu, H.L.; Yang, L.C. [Zhejiang University, Hangzhou (China). Dept. of Environmental Engineering

2009-12-15

92

Enoxaparin Improves the Course of Dextran Sodium Sulfate-Induced Colitis in Syndecan-1-Deficient Mice  

PubMed Central

Syndecan-1 (Sdc1) plays a major role in wound healing and modulates inflammatory responses. Sdc1 expression is reduced in lesions of patients with ulcerative colitis. The aim of this study was to investigate the role of Sdc1 in murine dextran sodium sulfate (DSS)-induced colitis. DSS colitis was induced in Sdc1-deficient (knockout (KO)) and wild-type mice by oral administration of 3% DSS. KO mice exhibited a significantly increased lethality as compared with wild-type controls (61 versus 5%, P < 0.05). Impaired mucosal healing and prolonged recruitment of inflammatory cells in KO mice were accompanied by significant up-regulation of tumor necrosis factor-?, CC chemokine ligand 3/macrophage inflammatory protein-1?, and vascular cell adhesion molecule-1, as determined by histological correlation between 0 and 15 days after colitis induction, TaqMan low-density array analysis, and quantitative real-time PCR. Treatment from days 7 through 14 with enoxaparin, a functional analogue of the Sdc1 heparan sulfate chains, significantly reduced lethality of KO mice due to DSS-induced colitis, which was correlated with improved mucosal healing. In vitro, Sdc1-deficient polymorphonuclear cells displayed increased adhesion to endothelial cells and intercellular adhesion molecule-1, and enoxaparin reverted adhesion to wild-type levels. Small interfering RNA-mediated knockdown of Sdc1 expression resulted in reduced basic fibroblast growth factor-mediated mitogen-activated protein kinase signaling and reduced Caco-2 cell proliferation. We conclude that Sdc1 has a protective effect during experimental colitis. The modification of missing Sdc1 function by heparin analogues may emerge as a promising anti-inflammatory approach. PMID:20008145

Floer, Martin; Gotte, Martin; Wild, Martin K.; Heidemann, Jan; Gassar, Ezeddin Salem; Domschke, Wolfram; Kiesel, Ludwig; Luegering, Andreas; Kucharzik, Torsten

2010-01-01

93

Chemical and physical properties of high-yield alkaline sulfite green liquor  

Microsoft Academic Search

The majority of sodium sulfite pulping liquor recovery systems are based on the reductive burning of the spent liquor, followed by acidification of the resulting smelt solution by CO[sub 2]. This study investigated a number of the physical and chemical properties of the resulting green liquor which might be relevant to the optimum design of this type of sulfite and

Nancy J. Sell; Jack C. Norman

1993-01-01

94

Self-Aggregation of Sodium Dodecyl Sulfate within (Choline Chloride + Urea) Deep Eutectic Solvent.  

PubMed

Deep eutectic solvents (DESs) have shown tremendous promise as green solvents with low toxicity and cost. Understanding molecular aggregation processes within DESs will not only enhance the application potential of these solvents but also help alleviate some of the limitations associated with them. Among DESs, those comprising choline chloride and appropriate hydrogen-bond donors are inexpensive and easy to prepare. On the basis of fluorescence probe, electrical conductivity, and surface tension experiments, we present the first clear lines of evidence for self-aggregation of an anionic surfactant within a DES containing a small fraction of water. Namely, well-defined assemblies of sodium dodecyl sulfate (SDS) apparently form in the archetype DES Reline comprising a 1:2 molar mixture of choline chloride and urea. Significant enhancement in the solubility of organic solvents that are otherwise not miscible in choline chloride-based DESs is achieved within Reline in the presence of SDS. The remarkably improved solubility of cyclohexane within SDS-added Reline is attributed to the presence of spontaneously formed cyclohexane-in-Reline microemulsions by SDS under ambient conditions. Surface tension, dynamic light scattering (DLS), small-angle X-ray scattering (SAXS), density, and dynamic viscosity measurements along with responses from the fluorescence dipolarity and microfluidity probes of pyrene and 1,3-bis(1-pyrenyl)propane are employed to characterize these aggregates. Such water-free oil-in-DES microemulsions are appropriately sized to be considered as a new type of nanoreactor. PMID:25314953

Pal, Mahi; Rai, Rewa; Yadav, Anita; Khanna, Rajesh; Baker, Gary A; Pandey, Siddharth

2014-11-11

95

Positive control for cytotoxicity evaluation of dental vinyl polysiloxane impression materials using sodium lauryl sulfate.  

PubMed

Abstract Objectives. Vinyl polysiloxane (VPS) is elastomeric dental impression material which, despite having very few reports of adverse reactions, has shown high levels of cytotoxicity that is difficult to be interpreted without referencing to the positive control material. Therefore, in this study, positive control VPS was developed using sodium lauryl sulfate (SLS) for the reference of cytotoxicity test. Materials and methods. The positive control VPS with SLS was formed with a different proportion of SLS (0, 1, 2, 4, 8 and 16 wt%) added to the base. The cytotoxicity test was then carried out using the extractions or dilutions of the extractions from each of the test samples using murine fibroblast cells (L929). Results. The final product of positive control VPS behaved similar to commercially available VPS; being initially liquid-like and then becoming rubber-like. Ion chromatography showed that the level of SLS released from the product increased as the proportion of added SLS increased, consequently resulting in an increased level of cytotoxicity. Also, the commercially available VPS was less cytotoxic than the positive control VPS with more or equal to 2 wt% of SLS. However, even the VPS with the highest SLS (16 wt%) did not cause oral mucosa irritation during the animal study. Conclusions. The positive control VPS was successfully produced using SLS, which will be useful in terms of providing references during in vitro cytotoxicity testing. PMID:24471730

Kwon, Jae-Sung; Lee, Sang-Bae; Kim, Kwang-Mahn; Kim, Kyoung-Nam

2014-11-01

96

Dietary Uptake of Wedelia chinensis Extract Attenuates Dextran Sulfate Sodium-Induced Colitis in Mice  

PubMed Central

Scope Traditional medicinal herbs are increasingly used as alternative therapies in patients with inflammatory diseases. Here we evaluated the effect of Wedelia chinensis, a medicinal herb commonly used in Asia, on the prevention of dextran sulfate sodium (DSS)-induced acute colitis in mice. General safety and the effect of different extraction methods on the bioactivity of W. chinensis were also explored. Methods and Results C57BL/6 mice were administrated hot water extract of fresh W. chinensis (WCHF) orally for one week followed by drinking water containing 2% DSS for nine days. WCHF significantly attenuated the symptoms of colitis including diarrhea, rectal bleeding and loss of body weight; it also reduced the shortening of colon length and histopathological damage caused by colonic inflammation. Among four W. chinensis extracts prepared using different extraction techniques, WCHF showed the highest anti-colitis efficacy. Analyses of specific T-cell regulatory cytokines (TNF-?, IL-4, IFN-?, IL-17, TGF-?, IL-12) revealed that WCHF treatment can suppress the Th1 and Th17, but not Th2, responses in colon tissues and dendritic cells of DSS-induced colitis mice. A 28-day subacute toxicity study showed that daily oral administration of WCHF (100, 500, 1000 mg/kg body weight) was not toxic to mice. Conclusion Together, our findings suggest that specific extracts of W. chinensis have nutritional potential for future development into nutraceuticals or dietary supplements for treatment of inflammatory bowel disease. PMID:23734189

Chen, Yung-Hsiang; Huang, Wen-Ching; Huang, Li-Ting; Lin, Wen-Ching; Arulselvan, Palanisamy; Liao, Jiunn-Wang; Lin, Shu-Hui; Hsiao, Pei-Wen; Kuo, Sheng-Chu; Yang, Ning-Sun

2013-01-01

97

Oleuropein protects against dextran sodium sulfate-induced chronic colitis in mice.  

PubMed

The anti-inflammatory effect of oleuropein (1), the major phenolic secoiridoid in Olea europaea, was evaluated in an experimental model of chronic colitis in mice. Animals were exposed to four repeated cycles of dextran sodium sulfate in drinking water followed by a 7-day rest period. Animals receiving a standard diet supplemented with 0.25% of 1 (equivalent to 500 mg/kg/day) for 56 days exhibited a decrease of inflammatory symptoms, as reflected by improvement of disease activity index and histopathological changes. It was found that 1 decreased inflammatory cell recruitment and the release of inflammatory cytokines interleukin (IL)-1? and IL-6 with increased IL-10 levels in colon tissue. Colon expression of cyclooxygenase-2 and inducible nitric oxide synthase was reduced significantly by 1. The anti-inflammatory molecular mechanism of 1 was associated with the suppression of the phosphorylation of p38 mitogen-activated protein kinase and might be mediated by up-regulation of annexin A1. In addition, 1 ameliorated intestinal wound healing in IEC-18 monolayers. Therefore, oleuropein seems to be a promising active molecule in experimental ulcerative colitis. PMID:23758110

Giner, Elisa; Recio, María-Carmen; Ríos, José-Luis; Giner, Rosa-María

2013-06-28

98

Feeding with olive oil attenuates inflammation in dextran sulfate sodium-induced colitis in rat.  

PubMed

Chronic inflammation of long-term ulcerative colitis contributes to an increased risk of colon cancer. Few studies address whether extra-virgin olive oil (EVOO) intake suppresses inflammation, cell proliferation and signal transducers and activators of transcription (STAT) in the experimental colitis model. The aim of this study was to assess whether a 5% EVOO suppressed inflammation, increased cell proliferation and the expressions of STAT3 and STAT3 phosphorylation (pSTAT3) in dextran sulfate sodium (DSS)-induced colitis. Rats were administered DSS via drinking water (weight percentage: 4%) for 1 week with a 1-week recovery period for three cycles. Rats were divided into three groups: control group, standard diet without DSS; DSS group, standard diet+DSS; and DSS+EVOO group, EVOO diet (weight percentage: 5%)+DSS. Rats were sacrificed 5 weeks after DSS was first administered, and colonic damage was histologically and biochemically evaluated. As a result, chronic feeding of 5% EVOO attenuated inflammation. This was evaluated using a disease activity index, body weight loss and a histological score. Enhanced expressions of STAT3, pSTAT3, COX-2 and iNOS by DSS was attenuated by EVOO. In addition, EVOO attenuated increases in cell proliferation (PCNA) caused by DSS and recovered decreases in apoptosis (cleaved caspase-3). In conclusion, the study indicated that chronic feeding of 5% EVOO inhibited chronic inflammation in DSS-induced colitis in rats and also attenuated cell proliferation and recovered apoptosis in DSS colitis. PMID:24445043

Takashima, Toru; Sakata, Yasuhisa; Iwakiri, Ryuichi; Shiraishi, Ryosuke; Oda, Yasutomo; Inoue, Norie; Nakayama, Atsushi; Toda, Shuji; Fujimoto, Kazuma

2014-02-01

99

Balsalazine decreases intestinal mucosal permeability of dextran sulfate sodium-induced colitis in mice  

PubMed Central

Aim: To investigate the effect of balsalazine treatment on intestinal mucosal permeability in dextran sulfate sodium (DSS)-induced colitis and to determine the mechanism of the balsalazine-induced changes. Methods: Experimental colitis was induced in C57BL/6J mice by the administration of 5% DSS. Balsalazine was administered intragastrically at doses of 42, 141, and 423 mg/kg. The disease activity index (DAI) score was evaluated and colon tissue was collected for the assessment of histological changes. The amount of malondialdehyde (MDA) in the colon was determined, along with the activity of myeloperoxidase (MPO), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). Mucosa from the small intestine was collected to determine the levels of tumor necrosis factor (TNF)-? and interferon (IFN)-?. The mucosa was ultrastructurally examined with transmission electron microscopy and intestinal permeability was assayed using Evans blue. Results: Balsalazine was found to reduce the DAI score and the histological index (HI) score, decrease the MDA content and the activity of MPO, and increase the activity of SOD and GSH-Px in colitis mice. At the same time, balsalazine ameliorated microvillus and tight junction structure, resulting in a decrease in the amount of Evans blue permeating into the intestinal wall and the levels of TNF-? and IFN-? in colitis mice. Conclusion: In colitis mice, the anti-colitis effect of balsalazine results in a decrease in intestinal mucosal permeability. The mechanism of this effect is partly associated with balsalazine's antioxidative and anti-inflammatory effects. PMID:19575002

Liu, Xiao-chang; Mei, Qiao; Xu, Jian-ming; Hu, Jing

2009-01-01

100

Suppression of Dextran Sulfate Sodium-Induced Colitis in Mice by Radon Inhalation  

PubMed Central

The enhanced release of reactive oxygen species from activated neutrophils plays important role in the pathogenesis of inflammatory bowel disease. We previously reported that radon inhalation activates antioxidative functions in various organs of mice. In this study, we examined the protective effects of radon inhalation on dextran sulfate sodium- (DSS) induced colitis in mice which were subjected to DSS for 7 days. Mice were continuously treated with air only (sham) or radon at a concentration of 2000?Bq/m3 from a day before DSS administration to the end of colitis induction. In the results, radon inhalation suppressed the elevation of the disease activity index score and histological damage score induced by DSS. Based on the changes in tumor necrosis factor-alpha in plasma and myeloperoxidase activity in the colon, it was shown that radon inhalation suppressed DSS-induced colonic inflammation. Moreover, radon inhalation suppressed lipid peroxidation of the colon induced by DSS. The antioxidant level (superoxide dismutase and total glutathione) in the colon after DSS administration was significantly higher in mice treated with radon than with the sham. These results suggested that radon inhalation suppressed DSS-induced colitis through the enhancement of antioxidative functions in the colon. PMID:23365486

Nishiyama, Yuichi; Kataoka, Takahiro; Yamato, Keiko; Taguchi, Takehito; Yamaoka, Kiyonori

2012-01-01

101

Thermodynamics of solubilization of pentanol in sodium dodecyl sulfate-dodecyldimethylamine oxide mixed micelles  

SciTech Connect

Heat capacity and density measurements of pentanol (PeOH)-sodium dodecyl sulfate (NaDS)-dodecyldimethylamine oxide-water mixtures were carried out at 0.03 m PeOH as a function of the total surfactants concentration (m[sub t]) at different ratios (X). From experimental data, the apparent molar volumes (V) and heat capacities (C) of PeOH in the surfactants mixture solutions were calculated. As a general feature, at a given mixture composition, V increases monotonically with m[sub t] as observed in pure surfactants. In the cases of X = 0.1 and 0.3, V drops at about 0.1 and 0.15 m, respectively. The decreasing C vs m[sub t] curve shows peculiarities which were ascribed to the presence of a liquid crystalline phase for X = 0.1 and 0.3 and of a structural micellar transition for X = 0.6 and 0.9. At a given X, the dependence of the apparent molar property of PeOH on m[sub t] was rationalized in terms of the distribution constant of alcohol between the aqueous and the micellar phases (K) and its partial molar property in the aqueous and the micellar phases. The standard free energy, calculated from the K values, and the partial molar properties of PeOH in the surfactant-surfactant micelles change linearly with X according to the ideal behavior.

Milioto, S.; Crisantino, R.; De Lisi, R. (Univ. di Palermo (Italy). Dept. di Chimica Fisica)

1994-09-01

102

Solubilities of ethane in aqueous solutions of sodium dodecyl sulfate at elevated pressures  

SciTech Connect

The solubilities of ethane in aqueous solutions of sodium dodecyl sulfate (SDS) were measured at 313.15 K and at pressures up to 3 MPa. The molalities of SDS (m{sub SDS}) in the aqueous solution were 0.0000, 0.0020, 0.0040, 0.0060, 0.0070, 0.0080, 0.0090, 0.0100, 0.0126, 0.0150, 0.0200, and 0.0300. The effect of SDS on the gas solubility in both concentration regions below and above the critical micelle concentration (cmc) was studied. The existence of the micelles of SDS in the solution is favorable to the dissolution of ethane due to the hydrocarbon-like interior of the micelles. The solubilities of ethane in each micelle at different pressures were evaluated based on some assumptions. It was found that the intramicellar solubility of ethane is less than that of the gas in n-dodecane. It was also found that the solubility of ethane in the micelles increases linearly with the partial pressure of ethane. The cmc of SDS was evaluated based on the solubility vs m{sub SDS} curves and the effect of dissolved ethane on the cmc was studied. It was observed that the cmc shifts toward a higher value with the increase in dissolved ethane.

Li, P. [Lanzhou Univ. (China). Dept. of Materials Science] [Lanzhou Univ. (China). Dept. of Materials Science; Han, B.; Yan, H.; Liu, R. [Academia Sinica, Beijing (China). Inst. of Chemistry] [Academia Sinica, Beijing (China). Inst. of Chemistry

1995-10-01

103

Chemical and mechanical stability of sodium sulfate activated slag after exposure to elevated temperature  

SciTech Connect

The chemical and mechanical stability of slag activated with two different concentrations of sodium sulfate (Na{sub 2}SO{sub 4}) after exposure to elevated temperatures ranging from 200 to 800 Degree-Sign C with an increment of 200 Degree-Sign C has been examined. Compressive strengths and pH of the hardened pastes before and after the exposure were determined. The various decomposition phases formed were identified using X-ray diffraction, thermogravimetric analysis and scanning electron microscopy. The results indicated that Na{sub 2}SO{sub 4} activated slag has a better resistance to the degradation caused by exposure to elevated temperature up to 600 Degree-Sign C than Portland cement system as its relative strengths are superior. The finer slag and higher Na{sub 2}SO{sub 4} concentration gave better temperature resistance. Whilst the pH of the hardened pastes decreased with an increase in temperature, it still maintained a sufficiently high pH for the protection of reinforcing bar against corrosion.

Rashad, A.M., E-mail: alaarashad@yahoo.com [Housing and Building National Research Center, HBRC, 87 El-Tahrir St., Dokki, Giza 11511, P.O. Box: 1770, Cairo (Egypt); Bai, Y., E-mail: y.bai@qub.ac.uk [School of Planning, Architecture and Civil Engineering, Queen's University Belfast, David Keir Building, Stranmillis Road, Belfast BT9 5AG (United Kingdom); Basheer, P.A.M. [School of Planning, Architecture and Civil Engineering, Queen's University Belfast, David Keir Building, Stranmillis Road, Belfast BT9 5AG (United Kingdom); Collier, N.C.; Milestone, N.B. [Immobilisation Science Laboratory, Department of Engineering Materials, University of Sheffield, Mappin Street, Sheffield S1 3JD (United Kingdom)

2012-02-15

104

Sodium dodecyl sulfate at water-hydrophobic interfaces: a simulation study.  

PubMed

Using molecular dynamics simulations, we have studied the water-vapor and water-oil (decane) interfaces of aqueous solutions of sodium dodecyl sulfate (SDS). The water-vapor interface is often used as a model for water-oil (hydrophobic) interfaces, yet we observe that the behavior of amphiphilic DS(-) ions at these two interfaces is very different. Specifically, on a water-vapor interface, SDS forms aggregates at low coverages, while it is homogeneously distributed on the water-oil interface. Two decane parametrizations resulted in dramatically different conformations: decane parametrized based on a GROMOS force field "froze", while decane parametrized with a TraPPE force field remained liquid at 300 K. The calculated effective second-order susceptibilities and nonlinear sum frequency scattering intensities of DS(-) ions at the "frozen" decane-water agree well with experimental data of DS(-) ions at the hexadecane droplet-water interface. This suggests that the orientation of longer alkane molecules is predominantly parallel to the interface and that, at low coverages, DS(-) ions follow the orientation of oil molecules. PMID:22998553

Vácha, Robert; Roke, Sylvie

2012-10-01

105

Anti-inflammatory effects of Inonotus obliquus in colitis induced by dextran sodium sulfate.  

PubMed

A total of 28 male BALB/c mice (average weight 20.7 +/- 1.6 g) were divided into 4 treatment groups and fed a commercial diet (A), a commercial diet + induced colitis by dextran sodium sulfate (DSS) (B), Inonotus obliquus (IO) administration (C), and IO administration + induced colitis by DSS (D). IO treatment (C, D) decreased the expression of tumor necrosis factor (TNF)-alpha and signal transducers and activators of transcription (STAT)1 compared to those of the colitis induced group (B). The expressions of IL-4 and STAT6 were decreased in group D compared to the colitis induced group (B). The serum immunoglobulin (Ig)E level decreased in IO treatment groups (C, D) compared to no IO treatment groups (A and B) although there was no significant difference between the IO treatment groups. Extract from IO itself had a weak cytotoxic effect on murine macrophage cell line (RAW264.7 cells). Extract from IO inhibited lipopolysaccharide- (LPS-) induced, TNF-alpha, STAT1, pSTAT1, STAT6, and pSTAT6 production in RAW264.7 cells. PMID:20300439

Choi, Se Young; Hur, Sun Jin; An, Chi Sun; Jeon, Yun Hui; Jeoung, Young Jun; Bak, Jong Phil; Lim, Beong Ou

2010-01-01

106

Anti-Inflammatory Effects of Inonotus obliquus in Colitis Induced by Dextran Sodium Sulfate  

PubMed Central

A total of 28 male BALB/c mice (average weight 20.7?±?1.6?g) were divided into 4 treatment groups and fed a commercial diet (A), a commercial diet + induced colitis by dextran sodium sulfate (DSS) (B), Inonotus obliquus (IO) administration (C), and IO administration + induced colitis by DSS (D). IO treatment (C, D) decreased the expression of tumor necrosis factor (TNF)-? and signal transducers and activators of transcription (STAT)1 compared to those of the colitis induced group (B). The expressions of IL-4 and STAT6 were decreased in group D compared to the colitis induced group (B). The serum immunoglobulin (Ig)E level decreased in IO treatment groups (C, D) compared to no IO treatment groups (A and B) although there was no significant difference between the IO treatment groups. Extract from IO itself had a weak cytotoxic effect on murine macrophage cell line (RAW264.7 cells). Extract from IO inhibited lipopolysaccharide- (LPS-) induced, TNF-?, STAT1, pSTAT1, STAT6, and pSTAT6 production in RAW264.7 cells. PMID:20300439

Choi, Se Young; Hur, Sun Jin; An, Chi Sun; Jeon, Yun Hui; Jeoung, Young Jun; Bak, Jong Phil; Lim, Beong Ou

2010-01-01

107

Compensatory response of colon tissue to dextran sulfate sodium-induced colitis.  

PubMed

Depletion of goblet cells (the main mucin-producing cells in the colon) is one of the most reliable histological characteristics of ulcerative colitis, whereas a major symptom of this disease is bloody diarrhea containing a large amount of mucus. The discrepancy between these phenomena was investigated in a time-course study in rats with experimental colitis induced by treatment with oral dextran sulfate sodium (DSS) for 1, 3, or 5 days. Biochemical analysis showed a reduction in mucin content in the distal side of the colon that was proportional to the duration of DSS administration. In the proximal side of the colon, however, there was a significant increase in mucin content already on the first day of treatment with DSS. This increase in colonic mucin content continued for the 5 days of treatment. In the distal side, both sulfomucin and sialomucin decreased proportionally to the duration of DSS administration. In the proximal side, there was an increase in high iron diamine-Alcian blue-positive mucins, and confirming the proliferation of goblet cells. The proliferated glands were predominantly sialylated. Goblet cell depletion and an increase in mucin production occurred in different parts of the colon. This phenomenon may be a type of compensatory function of colon tissue in response to the localized decrease of mucin production in certain portions of the colon. PMID:10213120

Nakano, S; Ohara, S; Kubota, T; Saigenji, K; Hotta, K

1999-04-01

108

Increased sensitivity to dextran sodium sulfate colitis in IRE1?-deficient mice  

PubMed Central

The epithelial cells of the gastrointestinal tract are exposed to toxins and infectious agents that can adversely affect protein folding in the endoplasmic reticulum (ER) and cause ER stress. The IRE1 genes are implicated in sensing and responding to ER stress signals. We found that epithelial cells of the gastrointestinal tract express IRE1?, a specific isoform of IRE1. BiP protein, a marker of ER stress, was elevated in the colonic mucosa of IRE1?–/– mice, and, when exposed to dextran sodium sulfate (DSS) to induce inflammatory bowel disease, mutant mice developed colitis 3–5 days earlier than did wild-type or IRE1?+/– mice. The inflammation marker ICAM-1 was also expressed earlier in the colonic mucosa of DSS-treated IRE1?–/– mice, indicating that the mutation had its impact early in the inflammatory process, before the onset of mucosal ulceration. These findings are consistent with a model whereby perturbations in ER function, which are normally mitigated by the activity of IRE1?, participate in the development of colitis. PMID:11238559

Bertolotti, Anne; Wang, XiaoZhong; Novoa, Isabel; Jungreis, Rivka; Schlessinger, Karni; Cho, Judy H.; West, A. Brian; Ron, David

2001-01-01

109

Mechanical properties of mouse lungs along organ decellularization by sodium dodecyl sulfate.  

PubMed

Lung decellularization is based on the use of physical, chemical, or enzymatic methods to break down the integrity of the cells followed by a treatment to extract the cellular material from the lung scaffold. The aim of this study was to characterize the mechanical changes throughout the different steps of lung decellularization process. Four lungs from mice (C57BL/6) were decellularized by using a conventional protocol based on sodium dodecyl sulfate. Lungs resistance (R(L)) and elastance (E(L)) were measured along decellularization steps and were computed by linear regression fitting of tracheal pressure, flow, and volume during mechanical ventilation. Transients differences found were more distinct in an intermediate step after the lungs were rinsed with deionized water and treated with 1% SDS, whereupon the percentage of variation reached approximately 80% for resistance values and 30% for elastance values. In conclusion, although a variation in extracellular matrix stiffness was observed during the decellularization process, this variation can be considered negligible overall because the resistance and elastance returned to basal values at the final decellularization step. PMID:24837837

Nonaka, Paula N; Uriarte, Juan J; Campillo, Noelia; Melo, Esther; Navajas, Daniel; Farré, Ramon; Oliveira, Luis V F

2014-08-15

110

Effect of sodium dodecyl sulfate on protein separation by hollow fiber flow field-flow fractionation.  

PubMed

Effects of protein denaturation and formation of protein-sodium dodecyl sulfate (SDS) complexes on protein separation and identification were investigated using hollow fiber flow field-flow fractionation (HF5) and nanoflow liquid chromatography-electrospray ionization-tandem mass spectrometry (nLC-ESI-MS-MS). Denaturation and formation of protein-SDS complexes prior to HF5 separation resulted an increase in the retention of few protein standards due to unfolding of the protein structures and complexation, yielding ~30% increase in hydrodynamic diameter. In addition, low molecular weight proteins which could be lost from the HF membrane due to the pore size limitation showed an increase of peak recovery about 2-6 folds for cytochrome C and carbonic anhydrase. In the case of proteins composed of a number of subunits, denaturation resulted in a decrease in retention due to dissociation of protein subunits. A serum proteome sample, denatured with dithiothreitol and SDS, was fractionated by HF5, and the eluting protein fractions after tryptic digestion were analyzed for protein identification using nLC-ESI-MS-MS. The resulting pools of identified proteins were found to depend on whether the serum sample was treated with or without denaturation prior to the HF5 run due to differences in the aqueous solubility of the proteins. The enhancement of protein solubility by SDS also increased the number of identified membrane proteins (54 vs. 31). PMID:20963232

Kim, Ki Hun; Lee, Ju Yong; Moon, Myeong Hee

2011-01-21

111

Microfluidic integration of Western blotting is enabled by electrotransfer-assisted sodium dodecyl sulfate dilution.  

PubMed

We integrate sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) with subsequent antibody probing in a single, monolithic microdevice to realize microfluidic Western blotting. A hurdle to successful on-chip Western blotting lies in restoring antibody recognition of previously sized (denatured, reduced) proteins. To surmount this hurdle, we locally dilute free SDS from SDS-protein complexes using differential electromigration of the species during electrotransfer between SDS-PAGE and blotting regions of a microchamber. Local dilution of SDS minimizes re-association of SDS with proteins offering means to restore antibody binding affinity to proteins after SDS-PAGE. To achieve automated, programmable operation in a single instrument, we utilize a 1 × 2 mm(2) glass microchamber photopatterned with spatially distinct, contiguous polyacrylamide regions for SDS-PAGE, electrotransfer, and antibody blotting. Optimization of both the SDS-PAGE and electrotransfer conditions yields transfer distances of <1 mm (40 s). The Western blot is completed in 180 s, with fully automated assay operation using programmable voltage control. After SDS-PAGE and electrotransfer, we observe ~80% capture of protein band mass on the blotting region for a model protein, C-reactive protein. This novel microfluidic Western blot approach introduces fine transport control for in-transit protein handling to form the basis for an automated, rapid alternative to conventional slab-gel Western blotting. PMID:23042290

Hou, Chenlu; Herr, Amy E

2013-01-01

112

New Perspective on Dextran Sodium Sulfate Colitis: Antigen-Specific T Cell Development during Intestinal Inflammation  

PubMed Central

CD4+ T cell responses against oral antigens can develop in inflammatory bowel disease (IBD) patients, which may modulate disease. Dextran sodium sulfate (DSS) colitis is commonly used to study IBD, however, it is not considered the best model in which to study T cell involvement in intestinal disease. Our aim was to determine if antigen-specific T cells could be induced during DSS colitis and if they could be detected after disease resolution. To induce antigen-specific T cells, the tracking antigen, ovalbumin (OVA), was administered orally during colitis initiation. Disease severity was monitored, and the antigen-reactivity of CD4+ T cells examined using CD69 expression. While OVA-directed, CD4+ Foxp3+ regulatory T cells could be detected in the spleens of both OVA-treated control and DSS mice, OVA-reactive, CD4+ Foxp3-T cells were only found in the OVA and DSS-treated mice. These results indicate that during DSS colitis T cells develop that are specific against oral antigens, and they are found systemically after colitis resolution. This gives added depth and utility to the DSS model as well as a way to track T cells that are primed against luminal antigens. PMID:23936123

Morgan, Mary E.; Zheng, Bin; Koelink, Pim J.; van de Kant, Hendrick J. G.; Haazen, Lizette C. J. M.; van Roest, Manon; Garssen, Johan; Folkerts, Gert; Kraneveld, Aletta D.

2013-01-01

113

Simple Sodium Dodecyl Sulfate-Assisted Sample Preparation Method for LC-MS-based Proteomic Applications  

SciTech Connect

Sodium dodecyl sulfate (SDS) is one of the most popular laboratory reagents used for highly efficient biological sample extraction; however, SDS presents a significant challenge to LC-MS-based proteomic analyses due to its severe interference with reversed-phase LC separations and electrospray ionization interfaces. This study reports a simple SDS-assisted proteomic sample preparation method facilitated by a novel peptide-level SDS removal protocol. After SDS-assisted protein extraction and digestion, SDS was effectively (>99.9%) removed from peptides through ion substitution-mediated DS- precipitation with potassium chloride (KCl) followed by {approx}10 min centrifugation. Excellent peptide recovery (>95%) was observed for less than 20 {mu}g of peptides. Further experiments demonstrated the compatibility of this protocol with LC-MS/MS analyses. The resulting proteome coverage from this SDS-assisted protocol was comparable to or better than those obtained from other standard proteomic preparation methods in both mammalian tissues and bacterial samples. These results suggest that this SDS-assisted protocol is a practical, simple, and broadly applicable proteomic sample processing method, which can be particularly useful when dealing with samples difficult to solubilize by other methods.

Zhou, Jianying; Dann, Geoffrey P.; Shi, Tujin; Wang, Lu; Gao, Xiaoli; Su, Dian; Nicora, Carrie D.; Shukla, Anil K.; Moore, Ronald J.; Liu, Tao; Camp, David G.; Smith, Richard D.; Qian, Weijun

2012-03-10

114

Overexpression of GATA-3 in T Cells Accelerates Dextran Sulfate Sodium-Induced Colitis  

PubMed Central

Ulcerative colitis (UC) is an inflammatory bowel disease, and its pathogenesis includes genetic, environmental, and immunological factors, such as T helper cells and their secreted cytokines. T helper cells are classified as Th1, Th2, and Th17 cells. However, it is unclear which T helper cells are important in UC. Dextran sulfate sodium (DSS)-induced colitis is a commonly used model of UC. In this study, we induced DSS colitis in Th1 dominant (T-bet transgenic (Tg)) mice, Th2 dominant (GATA-3 Tg) mice, and Th17 dominant (ROR?t Tg) mice to elucidate the roles of T helper cell in DSS colitis. The results showed that GATA-3 Tg mice developed the most severe DSS colitis compared with the other groups. GATA-3 Tg mice showed a significant decreased in weight from day 1 to day 7, and an increased high score for the disease activity index compared with the other groups. Furthermore, GATA-3 Tg mice developed many ulcers in the colon, and many neutrophils and macrophages were detected on day 4 after DSS treatment. Measurement of GATA-3-induced cytokines demonstrated that IL-13 was highly expressed in the colon from DSS-induced GATA-3 Tg mice. In conclusion, GATA-3 overexpression in T-cells and IL-13 might play important roles in the development of DSS colitis. PMID:24770638

Okamura, Midori; Yoh, Keigyou; Ojima, Masami; Morito, Naoki; Takahashi, Satoru

2014-01-01

115

Management of stomal varices with transvenous obliteration utilizing sodium tetradecyl sulfate foam sclerosis.  

PubMed

The management of parastomal varices is not established. Transjugular intrahepatic portosystemic shunt (TIPS) creation is the most commonly described treatment; however, the rebleed rate after TIPS is 21-37 %. The purpose of the study is to determine the effectiveness of transvenous obliteration using sodium tetradecyl sulfate (STS) and to describe a new simplified technique in obliterating these varices. Four patients are presented who underwent transvenous obliteration using STS. One was obliterated using balloon occlusion from the systemic veins, the second was obliterated without balloon from a transhepatic antegrade approach, and the last two patients were obliterated using the direct antegrade technique. This simplified technique requires only a micropuncture kit (not requiring balloons or coils) and ultrasound transducer compression of the systemic draining veins, relying on high portal pressure to keep the sclerosant confined to the varices. The sclerosant is essentially trapped between the portal pressure and the ultrasound-transducer compression (10-15 min). Technical success was achieved in all four patients without procedural or postprocedural complications and no rebleeding for a mean follow-up of 17 (range 2-33) months. Transvenous obliteration of parastomal varices utilizing STS as a sclerosant is safe and effective. The newly described technique is simple, feasible, and requires minimal equipment (no balloons or coils or catheters). PMID:24798128

Saad, Wael E A; Schwaner, Sandra; Lippert, Allison; Sabri, Saher S; Al-Osaimi, Abdullah; Matsumoto, Alan H; Angle, John F; Caldwell, Stephen

2014-12-01

116

Dispersion stability of functionalized graphene in aqueous sodium dodecyl sulfate solutions.  

PubMed

The colloidal stability of functionalized graphene sheets (FGSs) in aqueous sodium dodecyl sulfate (SDS) solutions of different concentrations was studied by optical microscopy and ultraviolet-visible light absorption after first dispersing the FGSs ultrasonically. In up to ?10 ?M SDS solutions, FGSs reaggregated within a few minutes, forming ramified structures in the absence of SDS and increasingly compact structures as the amount of SDS increased. Above ?10 ?M, the rate of reaggregation decreased with increasing SDS concentration; above ?40 ?M, the suspensions were colloidally stable for over a year. The concentration of ?40 ?M SDS lies 2 orders of magnitude below the critical surface aggregation concentration of ?1.8 mM SDS on FGSs but above the concentration (?18 ?M) at which SDS begins to form a monolayer on FGSs. Neither surface micelle nor dense monolayer coverage is therefore required to obtain stable aqueous FGS dispersions. We support our experimental results by calculating the van der Waals and electrostatic interaction energies between FGSs as a function of SDS concentration and show that the experimentally observed transition from an unstable to a stable dispersion correlates with a transition from negative to positive interaction energies between FGSs in the aggregated state. Furthermore, our calculations support experimental evidence that aggregates tend to develop a compact structure over time. PMID:24188504

Hsieh, Andrew G; Korkut, Sibel; Punckt, Christian; Aksay, Ilhan A

2013-12-01

117

Curcumin Inhibits STAT3 Signaling in the Colon of Dextran Sulfate Sodium-treated Mice  

PubMed Central

Turmeric (Curcuma longa L., Zingiberaceae) has a long history of use in medicine for the treatment of inflammatory conditions. One of the major constituents of turmeric is curcumin (diferuloylmethane), which is responsible for its characteristic yellow color. In the present study, we have examined the chemoprotective effects of curcuminon dextran sulfate sodium (DSS)-induced mouse colitis. For this purpose, we pre-treated male ICR mice with curcumin (0.1 or 0.25 mmol/kg in 0.05% carboxymethyl cellulose) by gavage for a week and then co-treated the animals with curcumin by gavage and 3% DSS in drinking water for another 7 days. Our study revealed that administration of curcumin significantly attenuated the severity of DSS-induced colitis and STAT3 signaling in mouse colon. The levels of the cell cycle regulators CDK4 and cylinD1 were significantly reduced by curcumin administration. Moreover, the expression of p53, which is an upstream regulator of the CDK4-cylinD1 complex, was inhibited by curcumin treatment. PMID:25337545

Yang, Joon-Yeop; Zhong, Xiancai; Yum, Hye-Won; Lee, Hyung-Jun; Kundu, Joydeb Kumar; Na, Hye-Kyung; Surh, Young-Joon

2013-01-01

118

Sodium dodecyl sulfate-polyacrylamide gel protein electrophoresis of freshwater photosynthetic sulfur bacteria.  

PubMed

Sodium dodecyl sulfate-polyacrylamide gel protein electrophoresis (SDS-PAGE) was carried out using different bacterial strains of the photosynthetic sulfur bacteria Chlorobium, Thiocapsa, Thiocystis, and Chromatium cultured in the laboratory, and the natural blooms in two karstic lakes (Lake Cisó and Lake Vilar, NE Spain) where planktonic photosynthetic bacteria (purple and green sulfur bacteria) massively developed accounting for most of the microbial biomass. Several extraction, solubilization, and electrophoresis methods were tested to develop an optimal protocol for the best resolution of the SDS-PAGE. Protein composition from different water depths and at different times of the year was visualized within a molecular mass range between 100 and 15 kDa yielding up to 20 different protein bands. Protein banding patterns were reproducible and changed in time and with depth in agreement with changes in photosynthetic bacteria composition. When a taxonomically stable community was followed in time, differences were observed in the intensity but not in the composition of the SDS-PAGE banding pattern. Three environmental variables directly related to the activity of sulfur bacteria (light, oxygen, and sulfide concentrations) had a significant effect on protein banding patterns and explained 33% of the variance. Changes in natural protein profiles of the bacterial blooms agreed with changes in species composition and in the in situ metabolic state of the populations. PMID:20524118

Osuna, M Begoña; Casamayor, Emilio O

2011-01-01

119

Fabrication and surface properties of hydrophobic barium sulfate aggregates based on sodium cocoate modification  

NASA Astrophysics Data System (ADS)

Hydrophobic barium sulfate aggregates were fabricated by the direction of cocoate anions. At 30 °C, when the weight ratio of sodium cocoate to BaSO4 particles was 2.0 wt.%, the active ratio of the product reached 99.43% and the contact angle was greater than 120°. This method could not only simplify the complex modification process, but reduce energy consumption. The surface morphology, chemical structure and composition of BaSO4 aggregates were characterized by SEM, XRD, and FTIR. The results indicated that the as-synthesized BaSO4 particles were almond-liked and were composed of many interconnected nanoballs and that their surfaces were affected by cocoate anions. The adsorption of cocoate anions reversed the charge and weakened the surface polarity of BaSO4 particles, driving the formation of aggregates. And cocoate anions induced a change of the BaSO4 particles surface from hydrophilic to hydrophobic by a self-assembly and transformation process. Due to the self-assembled structure and the surface hydrophobicity, when adding the hydrophobic BaSO4 into PVC, the mechanical properties of PVC composite materials were significantly improved.

Hu, Linna; Wang, Guangxiu; Cao, Rong; Yang, Chun; Chen, Xi

2014-10-01

120

Effect of n-pentanol on the solubility of ethane in micellar solutions of sodium dodecyl sulfate  

SciTech Connect

Experiments have been carried out to determine the effect that added n-pentanol has upon the solubility of ethane gas in micellar solutions of sodium dodecyl sulfate. The results show that when micellar sodium dodecyl sulfate is present, n-pentanol acts to enhance gas solubility. However, the degree to which the alcohol enhances gas solubility varies with concentration. At low concentrations, the incremental increase in ethane solubility per mole of alcohol is found to be numerically about equal to the solubility of ethane in ethanol. This incremental change in gas solubility increases with pentanol concentration and approaches the solubility of ethane in pure pentanol at high ratios of alcohol to surfactant. Unusual gas-induced gels are formed at moderate pressures (p is approx. 5 atm) with ethane and homogeneous solutions having compositions bordering those of the liquid crystal-solution phase boundary.

Hoskins, J.C.; King, A.D. Jr.

1981-07-01

121

An essential role for tomato sulfite oxidase and enzymes of the sulfite network in maintaining leaf sulfite homeostasis.  

PubMed

Little is known about the homeostasis of sulfite levels, a cytotoxic by-product of plant sulfur turnover. By employing extended dark to induce catabolic pathways, we followed key elements of the sulfite network enzymes that include adenosine-5'-phosphosulfate reductase and the sulfite scavengers sulfite oxidase (SO), sulfite reductase, UDP-sulfoquinovose synthase, and ?-mercaptopyruvate sulfurtransferases. During extended dark, SO was enhanced in tomato (Solanum lycopersicum) wild-type leaves, while the other sulfite network components were down-regulated. SO RNA interference plants lacking SO activity accumulated sulfite, resulting in leaf damage and mortality. Exogenous sulfite application induced up-regulation of the sulfite scavenger activities in dark-stressed or unstressed wild-type plants, while expression of the sulfite producer, adenosine-5'-phosphosulfate reductase, was down-regulated. Unstressed or dark-stressed wild-type plants were resistant to sulfite applications, but SO RNA interference plants showed sensitivity and overaccumulation of sulfite. Hence, under extended dark stress, SO activity is necessary to cope with rising endogenous sulfite levels. However, under nonstressed conditions, the sulfite network can control sulfite levels in the absence of SO activity. The novel evidence provided by the synchronous dark-induced turnover of sulfur-containing compounds, augmented by exogenous sulfite applications, underlines the role of SO and other sulfite network components in maintaining sulfite homeostasis, where sulfite appears to act as an orchestrating signal molecule. PMID:23148079

Brychkova, Galina; Grishkevich, Vladislav; Fluhr, Robert; Sagi, Moshe

2013-01-01

122

Effects of various polyoxyethylene sorbitan monooils (Tweens) and sodium dodecyl sulfate on reflux synthesis of copper nanoparticles  

SciTech Connect

Size-controlled synthesis of phase pure Cu nanoparticles was carried out by using copper sulfate pentahydrate as a precursor, ascorbic acid as a reductant, Tweens and sodium dodecyl sulfate (SDS) as modifiers in an aqueous solution at 80 deg. C. The as-prepared Cu nanoparticles were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and Fourier transform infrared (FT-IR). The stabilizing effects of SDS and Tweens on the Cu nanoparticles should be through the coordination between Cu nanoparticles and the respective sulfate group and oxygen-containing bond. The synergic effect of the composite SDS and Tweens on Cu nanoparticles was different from those arising from the individuals.

Zhang Xifeng [School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang, 212013 (China); Yin Hengbo [School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang, 212013 (China)]. E-mail: yin@ujs.edu.cn; Cheng Xiaonong [School of Material Science and Engineering, Jiangsu University, Zhenjiang, 212013 (China); Hu Huifeng [School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang, 212013 (China); Yu Qi [School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang, 212013 (China); Wang Aili [School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang, 212013 (China)

2006-11-09

123

Voluntary exercise inhibits intestinal tumorigenesis in ApcMin\\/+ mice and azoxymethane\\/dextran sulfate sodium-treated mice  

Microsoft Academic Search

BACKGROUND: Epidemiological studies suggest that physical activity reduces the risk of colon cancer in humans. Results from animal studies, however, are inconclusive. The present study investigated the effects of voluntary exercise on intestinal tumor formation in two different animal models, ApcMin\\/+ mice and azoxymethane (AOM)\\/dextran sulfate sodium (DSS)-treated mice. METHODS: In Experiments 1 and 2, five-week old female ApcMin\\/+ mice

Jihyeung Ju; Bonnie Nolan; Michelle Cheh; Mousumi Bose; Yong Lin; George C Wagner; Chung S Yang

2008-01-01

124

Effects of the supplementation of trehalose extender containing egg yolk with sodium dodecyl sulfate on the freezability of goat spermatozoa  

Microsoft Academic Search

Two experiments were conducted to determine the effect of sodium dodecyl sulfate (SDS) added to a trehalose-egg yolk extender on the cryopreservation of goat spermatozoa. In Experiment 1, semen from four goats was frozen in trehalose extender (osmolality=370, pH=7) containing 4 and 20% (v\\/v) glycerol and egg yolk, respectively, and 0.035–0.2% SDS. After thawing, sperm motility and acrosome integrity were

Eiman Mohamed-Elkheir Aboagla; Takato Terada

2004-01-01

125

Protective Effect of IntraRectal Administration of Rebamipide on Dextran Sulfate Sodium-Induced Rat Colitis  

Microsoft Academic Search

Background\\/Aim: Rebamipide, an anti-ulcer drug, has various actions including radical scavenging and mucus-stimulating as well as anti-inflammatory effects, and exhibits both mucosal protective and healing promoting actions in the stomach. In the present study, we examined the effect of rebamipide on an animal model of colitis induced by dextran sulfate sodium (DSS). Methods: Experimental colitis was induced in rats by

Mitsuaki Okayama; Ryoichi Tsubouchi; Hikaru Nishio; Shinichi Kato; Koji Takeuchi

2004-01-01

126

Corrosion resistance of sodium sulfate coated cobalt-chromium-aluminum alloys at 900 C, 1000 C, and 1100 C  

NASA Technical Reports Server (NTRS)

The corrosion of sodium sulfate coated cobalt alloys was measured and the results compared to the cyclic oxidation of alloys with the same composition, and to the hot corrosion of compositionally equivalent nickel-base alloys. Cobalt alloys with sufficient aluminum content to form aluminum containing scales corrode less than their nickel-base counterparts. The cobalt alloys with lower aluminum levels form CoO scales and corrode more than their nickel-base counterparts which form NiO scales.

Santoro, G. J.

1979-01-01

127

A conductometric study of dimethylsulfoxide effect on micellization of sodium dodecyl sulfate in dilute aqueous electrolyte solutions  

Microsoft Academic Search

Critical micelle concentrations (CMCs) of sodium dodecyl sulfate (SDS) have been determined in aqueous mixtures of dimethylsulfoxide (DMSO) between 25 and 45°C and at very low NaBr concentration range (0.0025–0.03 mol dm?3). The ability of NaBr to lower the CMC in water is inhibited by DMSO below ?0.014 mol dm?3 of NaBr. However, the contribution of DMSO in regard to

M. S Chauhan; K Sharma; G Kumar; S Chauhan

2003-01-01

128

Amelioration of dextran sulfate sodium–induced colitis by anti-macrophage migration inhibitory factor antibody in mice  

Microsoft Academic Search

Background & Aims: We investigated the effects of macrophage migration inhibitory factor (MIF) antibodies in experimental colitis-induced dextran sulfate sodium (DSS) and trinitrobenzenesulfonic acid (TNBS) and examined whether plasma levels of MIF were elevated in patients with inflammatory bowel disease (IBD). Methods: BALB\\/c or C57BL\\/6 mice were fed 4% DSS in their drinking water for up to 7 days with

Tatsuya Ohkawara; Jun Nishihira; Hiroshi Takeda; Shuhei Hige; Mototsugu Kato; Toshiro Sugiyama; Toshihiko Iwanaga; Hideki Nakamura; Yuka Mizue; Masahiro Asaka

2002-01-01

129

(Bi)sulfite Oxidation by Copper,Zinc-Superoxide Dismutase: Sulfite-Derived, Radical-Initiated Protein Radical Formation  

PubMed Central

Background Sulfur dioxide, formed during the combustion of fossil fuels, is a major air pollutant near large cities. Its two ionized forms in aqueous solution, sulfite and (bi)sulfite, are widely used as preservatives and antioxidants to prevent food and beverage spoilage. (Bi)sulfite can be oxidized by peroxidases to form the very reactive sulfur trioxide anion radical (•SO3?). This free radical further reacts with oxygen to form the peroxymonosulfate anion radical (?O3SOO•) and sulfate anion radical (SO4• ?). Objective To explore the critical role of these radical intermediates in further oxidizing biomolecules, we examined the ability of copper,zinc-superoxide dismutase (Cu,Zn-SOD) to initiate this radical chain reaction, using human serum albumin (HSA) as a model target. Methods We used electron paramagnetic resonance, optical spectroscopy, oxygen uptake, and immuno-spin trapping to study the protein oxidations driven by sulfite-derived radicals. Results We found that when Cu,Zn-SOD reacted with (bi)sulfite, •SO3? was produced, with the concomitant reduction of SOD-Cu(II) to SOD-Cu(I). Further, we demonstrated that sulfite oxidation mediated by Cu,Zn-SOD induced the formation of radical-derived 5,5-dimethyl-1-pyrroline N-oxide (DMPO) spin-trapped HSA radicals. Conclusions The present study suggests that protein oxidative damage resulting from (bi)sulfite oxidation promoted by Cu,Zn-SOD could be involved in oxidative damage and tissue injury in (bi)sulfite-exacerbated allergic reactions. PMID:20348042

Ranguelova, Kalina; Bonini, Marcelo G.; Mason, Ronald P.

2010-01-01

130

Application of the Aqueous Porous Pathway Model to Quantify the Effect of Sodium Lauryl Sulfate on Ultrasound-Induced Skin Structural Perturbation  

E-print Network

This study investigated the effect of sodium lauryl sulfate (SLS) on skin structural perturbation when utilized simultaneously with low-frequency sonophoresis (LFS). Pig full-thickness skin (FTS) and pig split-thickness ...

Polat, Baris E.

131

Transport Pathways and Enhancement Mechanisms within Localized and Non-Localized Transport Regions in Skin Treated with Low-Frequency Sonophoresis and Sodium Lauryl Sulfate  

E-print Network

Recent advances in transdermal drug delivery utilizing low-frequency sonophoresis (LFS) and sodium lauryl sulfate (SLS) have revealed that skin permeability enhancement is not homogenous across the skin surface. Instead, ...

Polat, Baris E.

132

Bifidobacterium breve Attenuates Murine Dextran Sodium Sulfate-Induced Colitis and Increases Regulatory T Cell Responses  

PubMed Central

While some probiotics have shown beneficial effects on preventing or treating colitis development, others have shown no effects. In this study, we have assessed the immunomodulating effects of two probiotic strains, Lactobacillus rhamnosus (L. rhamnosus) and Bifidobacterium breve (B. breve) on T cell polarization in vitro, using human peripheral blood mononuclear cells (PBMC), and in vivo, using murine dextran sodium sulfate (DSS) colitis model. With respect to the latter, the mRNA expression of T cell subset-associated transcription factors and cytokines in the colon was measured and the T helper type (Th) 17 and regulatory T cell (Treg) subsets were determined in the Peyer's patches. Both L. rhamnosus and B. breve incubations in vitro reduced Th17 and increased Th2 cell subsets in human PBMCs. In addition, B. breve incubation was also able to reduce Th1 and increase Treg cell subsets in contrast to L. rhamnosus. In vivo intervention with B. breve, but not L. rhamnosus, significantly attenuated the severity of DSS-induced colitis. In DSS-treated C57BL/6 mice, intervention with B. breve increased the expression of mRNA encoding for Th2- and Treg-associated cytokines in the distal colon. In addition, intervention with B. breve led to increases of Treg and decreases of Th17 cell subsets in Peyer's patches of DSS-treated mice. B. breve modulates T cell polarization towards Th2 and Treg cell-associated responses in vitro and in vivo. In vivo B. breve intervention ameliorates DSS-induced colitis symptoms and this protective effect may mediated by its effects on the T-cell composition. PMID:24787575

Zheng, Bin; van Bergenhenegouwen, Jeroen; Overbeek, Saskia; van de Kant, Hendrik J. G.; Garssen, Johan; Folkerts, Gert; Vos, Paul; Morgan, Mary E.; Kraneveld, Aletta D.

2014-01-01

133

Interactions of small dendrimers with sodium dodecyl sulfate at the air-water interface.  

PubMed

We have determined how the bulk behavior of mixtures of small cationic poly(amidoamine) dendrimers (generation 2, PAMAM-G2) and sodium dodecyl sulfate (SDS) affects the structure and composition of the adsorbed layers at the air-water interface. The aim is to reveal how the size of a well-defined hyperbranched polyelectrolyte affects the interfacial and bulk solution behavior of mixtures with oppositely charged surfactants, when the size of the polyelectrolyte approaches that of the surfactant. A combination of electrophoretic mobility, UV-vis spectroscopy, dynamic light scattering, and small-angle X-ray scattering measurements have been employed to characterize the interactions in the bulk solution. PAMAM-G2 associates strongly with SDS in the bulk, forming large aggregates where the size and the charge depend on the bulk composition. We show that kinetically trapped aggregates can be formed at compositions outside the equilibrium two-phase region, and the positively charged aggregates are larger than the negative ones. Surface tensiometry, neutron reflectometry, and ellipsometry have been used to reveal the properties of the interfacial layers. The interfacial structures formed depend strongly on the bulk composition: structured layers are present for samples inside the two-phase region, whereas intact nanostructured aggregates adsorb for samples just outside the two-phase region. The interfacial behavior of PAMAM-G2/SDS mixtures is compared with that of small amines or multivalent ions and oppositely charged surfactants. The implications of aggregate adsorption, dissociation, and spreading processes are discussed as well as the potential of small dendrimers for applications involving the delivery of functional molecules to interfaces. PMID:25203770

Yanez Arteta, Marianna; Campbell, Richard A; Watkins, Erik B; Obiols-Rabasa, Marc; Schillén, Karin; Nylander, Tommy

2014-10-01

134

Stepwise degradation of serum low denisty lipoprotein by sodium dodecyl sulfate.  

PubMed

The structure of human serum low density lipoprotein (LDL) was investigated by perturbing the LDL structure with sodium dodecyl sulfate (SDS). The change in LDL structure induced by the addition of SDS was monitored by sedimentation velocity measurements, ultraviolet difference spectroscopy, fluorescence spectroscopy and proteolytic digestion of apo-LDL with subtilisin BPN' [EC 3.4.21.14]. As the concentration of SDS was increased from 0.1 mg/ml to 3 mg/ml with LDL concentrations between 2.0 mg/ml and 4.4 mg/ml, the sedimentation coefficient of LDL changed in three distinct steps. It was found by chemical analyses that not more than 30% of the total lipid was lost from LDL in the second step, whereas the final step in the change of sedimentation coefficient corresponded to the complete removal of apo-LDL from the constituent lipids of LDL. The ultraviolet difference spectrum between the native and SDS-treated LDL and the quenching of LDL fluorescence underwent about 80% of the total change while the SDS concentration was only sufficient to cause the second of the three step changes in sedimentation coefficient. SDS-polyacrylamide gel electrophoresis of apo-LDL treated with subtilisin BPN' also showed that more than 70% of apo-LDL became susceptible to proteolysis under the same conditions. These results were interpreted as indicating that the solubilization of 20 to 30% of the lipids on the surface of LDL exposed nearly 80% or more of apo-LDL to the solvent. A small portion of apo-LDL was, however, still firmly anchored to the remaining lipid micelle as long as the concentration of SDS was less than that required to cause the final step of the change in sedimentation coefficient. PMID:181373

Ikai, A

1976-03-01

135

Oligonol Inhibits Dextran Sulfate Sodium-Induced Colitis and Colonic Adenoma Formation in Mice  

PubMed Central

Abstract Aims: To evaluate the effects of oligonol administration on experimentally induced colitis and colonic adenoma formation. Results: Oral administration of oligonol protected against mouse colitis induced by dextran sulfate sodium (DSS). Under the same experimental conditions, oligonol administration significantly inhibited the activation of nuclear factor-kappa B and signal transducer and activator of transcription (STAT) 3 and expression of cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and cyclin D1 in the mouse colon. Further, oligonol inhibited azoxymethane-initiated and DSS-promoted adenoma formation in the mouse colon. Oligonol administration also attenuated lipid peroxidation (malondialdehyde) and protein oxidation (4-hydroxy-2-nonenal), thereby preventing oxidative stress-induced apoptosis of colonic epithelial cells. In vitro studies demonstrated that oligonol treatment reduced lipopolysaccharide-induced expression of interleukin (IL)-1?, tumor necrosis factor ?, il-6, cox-2, and inos in murine macrophage RAW 264.7 cells. In another study, oligonol upregulated the antioxidant gene expression in the intestinal epithelial CCD841CoN cells and in the mouse colon. Innovation: Oligonol, an innovative formulation of catechin-type oligomers derived from the lychee fruit extract, was tested in this study for the first time to evaluate its effects on experimentally induced colitis and colonic adenoma formation in mice. Conclusion: Oligonol is effective in protecting against DSS-induced mouse colitis and colon carcinogenesis, suggesting that this polyphenol formulation may have a potential for the amelioration of inflammatory bowel disease and related disorders. Antioxid. Redox Signal. 19, 102–114. PMID:23394584

Yum, Hye-Won; Zhong, Xiancai; Park, Jin; Na, Hye-Kyung; Kim, Nayoung; Lee, Hye Seung

2013-01-01

136

Dietary flaxseed intake exacerbates acute colonic mucosal injury and inflammation induced by dextran sodium sulfate.  

PubMed

Flaxseed (FS), a dietary oilseed, contains a variety of anti-inflammatory bioactives, including fermentable fiber, phenolic compounds (lignans), and the n-3 polyunsaturated fatty acid (PUFA) ?-linolenic acid. The objective of this study was to determine the effects of FS and its n-3 PUFA-rich kernel or lignan- and soluble fiber-rich hull on colitis severity in a mouse model of acute colonic inflammation. C57BL/6 male mice were fed a basal diet (negative control) or a basal diet supplemented with 10% FS, 6% kernel, or 4% hull for 3 wk prior to and during colitis induction via 5 days of 2% (wt/vol) dextran sodium sulfate (DSS) in their drinking water (n = 12/group). An increase in anti-inflammatory metabolites (hepatic n-3 PUFAs, serum mammalian lignans, and cecal short-chain fatty acids) was associated with consumption of all FS-based diets, but not with anti-inflammatory effects in DSS-exposed mice. Dietary FS exacerbated DSS-induced acute colitis, as indicated by a heightened disease activity index and an increase in colonic injury and inflammatory biomarkers [histological damage, apoptosis, myeloperoxidase, inflammatory cytokines (IL-6 and IL-1?), and NF-?B signaling-related genes (Nfkb1, Ccl5, Bcl2a1a, Egfr, Relb, Birc3, and Atf1)]. Additionally, the adverse effect of the FS diet was extended systemically, as serum cytokines (IL-6, IFN?, and IL-1?) and hepatic cholesterol levels were increased. The adverse effects of FS were not associated with alterations in fecal microbial load or systemic bacterial translocation (endotoxemia). Collectively, this study demonstrates that although consumption of a 10% FS diet enhanced the levels of n-3 PUFAs, short-chain polyunsaturated fatty acids, and lignans in mice, it exacerbated DSS-induced colonic injury and inflammation. PMID:24763556

Zarepoor, Leila; Lu, Jenifer T; Zhang, Claire; Wu, Wenqing; Lepp, Dion; Robinson, Lindsay; Wanasundara, Janitha; Cui, Steve; Villeneuve, Sébastien; Fofana, Bourlaye; Tsao, Rong; Wood, Geoffrey A; Power, Krista A

2014-06-15

137

Sodium Dodecyl Sulfate Adsorption onto Positively Charged Surfaces: Monolayer Formation With Opposing Headgroup Orientations  

PubMed Central

The adsorption and structure of sodium dodecyl sulfate (SDS) layers onto positively charged films have been monitored in situ with vibrational sum-frequency-generation (SFG) spectroscopy and surface plasmon resonance (SPR) sensing. Substrates with different charge densities and polarities used in these studies include CaF2 at different pH values as well as allylamine and heptylamine films deposited onto CaF2 and Au substrates by radio frequency glow discharge deposition. The SDS films were adsorbed from aqueous solutions ranging in concentration from 0.067 to 20 mM. In general the SFG spectra exhibited well resolved CH and OH peaks. However, at SDS concentrations between 1–8 mM the SFG CH and OH intensities decreased close to background levels. Combined data sets from molecular conformation, orientation, and order sensitive SFG with mass sensitive SPR suggest that the observed changes in SFG intensities above 0.2 mM are related to structural arrangements in the SDS layer. A model is proposed where the SFG intensity minimum between 1–8 mM is associated with a monolayer containing two head group orientations, one pointing towards the substrate and one pointing towards the solution phase. The SFG peaks observed at concentrations below 0.2 mM are dominated by the presence of adsorbed contaminants such as fatty alcohols (e.g., dodecanol), which are more surface active than SDS. As SDS solution concentration is increased above 1 mM SDS molecules are incorporated in the surface layer, with dodecanol continuing to be present in the surface layer for solution concentrations up to at least critical micelle concentration. PMID:24024777

Song, Sang-Hun; Koelsch, Patrick; Weidner, Tobias; Wagner, Matthew S.; Castner, David G.

2013-01-01

138

Bifidobacterium breve attenuates murine dextran sodium sulfate-induced colitis and increases regulatory T cell responses.  

PubMed

While some probiotics have shown beneficial effects on preventing or treating colitis development, others have shown no effects. In this study, we have assessed the immunomodulating effects of two probiotic strains, Lactobacillus rhamnosus (L. rhamnosus) and Bifidobacterium breve (B. breve) on T cell polarization in vitro, using human peripheral blood mononuclear cells (PBMC), and in vivo, using murine dextran sodium sulfate (DSS) colitis model. With respect to the latter, the mRNA expression of T cell subset-associated transcription factors and cytokines in the colon was measured and the T helper type (Th) 17 and regulatory T cell (Treg) subsets were determined in the Peyer's patches. Both L. rhamnosus and B. breve incubations in vitro reduced Th17 and increased Th2 cell subsets in human PBMCs. In addition, B. breve incubation was also able to reduce Th1 and increase Treg cell subsets in contrast to L. rhamnosus. In vivo intervention with B. breve, but not L. rhamnosus, significantly attenuated the severity of DSS-induced colitis. In DSS-treated C57BL/6 mice, intervention with B. breve increased the expression of mRNA encoding for Th2- and Treg-associated cytokines in the distal colon. In addition, intervention with B. breve led to increases of Treg and decreases of Th17 cell subsets in Peyer's patches of DSS-treated mice. B. breve modulates T cell polarization towards Th2 and Treg cell-associated responses in vitro and in vivo. In vivo B. breve intervention ameliorates DSS-induced colitis symptoms and this protective effect may mediated by its effects on the T-cell composition. PMID:24787575

Zheng, Bin; van Bergenhenegouwen, Jeroen; Overbeek, Saskia; van de Kant, Hendrik J G; Garssen, Johan; Folkerts, Gert; Vos, Paul; Morgan, Mary E; Kraneveld, Aletta D

2014-01-01

139

Kimchi protects against azoxymethane/dextran sulfate sodium-induced colorectal carcinogenesis in mice.  

PubMed

The chemopreventive effects of different types and quantities of kimchi prepared with different subingredients, including commercial kimchi (CK), standardized kimchi (SK), cancer-preventive kimchi (CPK), and anticancer kimchi (ACK), on colorectal carcinogenesis in mice were evaluated. The development of colon cancer was induced in male BALB/c mice with a single intraperitoneal injection of azoxymethane (AOM, 10?mg/kg body weight) and subsequent treatment with 2% dextran sulfate sodium (DSS) in drinking water for 7 days for two cycles. After exposure to AOM and DSS, treatment with the methanolic extracts from different kimchis, particularly 1.89?g/kg of ACK, significantly increased colon length, decreased the ratio of colon weight/length, and resulted in the lowest number of tumors compared with the other kimchi-treated groups. Histological observation revealed that ACK was able to suppress AOM- and DSS-induced colonic mucosal damage and neoplasia. ACK also significantly decreased the mRNA levels of proinflammatory cytokines (TNF-?, IL-6, and IFN-?) as well as the mRNA and protein expression of inducible nitric oxide synthase and cyclooxygenase-2 (COX-2). In addition, the mRNA and protein expression of p53 and p21 was elevated in colon tissues from the ACK-treated mice compared with the other kimchi-treated groups. Our results suggest that kimchi exerted a suppressive effect on AOM- and DSS-induced colorectal carcinogenesis in the BALB/c mice. The anticancer effects of ACK were particularly potent. Thus, it is possible that the health-promoting subingredients added to ACK might be used to prevent colon carcinogenesis in humans. PMID:25029638

Kim, Hee-Young; Song, Jia-Le; Chang, Hee-Kyung; Kang, Soon-Ah; Park, Kun-Young

2014-08-01

140

Marine Hydroquinone Zonarol Prevents Inflammation and Apoptosis in Dextran Sulfate Sodium-Induced Mice Ulcerative Colitis  

PubMed Central

Background and Aim We previously identified an anti-inflammatory compound, zonarol, a hydroquinone isolated from the brown algae Dictyopteris undulata as a marine natural product. To ascertain the in vivo functions of zonarol, we examined the pharmacological effects of zonarol administration on dextran sulfate sodium (DSS)-induced inflammation in a mouse model of ulcerative colitis (UC). Our goal is to establish a safe and effective cure for inflammatory bowel disease (IBD) using zonarol. Methods and Results We subjected Slc:ICR mice to the administration of 2% DSS in drinking water for 14 days. At the same time, 5-aminosalicylic acid (5-ASA) at a dose of 50 mg/kg (positive control) and zonarol at doses of 10 and 20 mg/kg, were given orally once a day. DSS-treated animals developed symptoms similar to those of human UC, such as severe bloody diarrhea, which were evaluated by the disease activity index (DAI). Treatment with 20 mg/kg of zonarol, as well as 5-ASA, significantly suppressed the DAI score, and also led to a reduced colonic ulcer length and/or mucosal inflammatory infiltration by various immune cells, especially macrophages. Zonarol treatment significantly reduced the expression of pro-inflammatory signaling molecules, and prevented the apoptosis of intestinal epithelial cells. Finally, zonarol protected against in vitro lipopolysaccharide (LPS)-induced activation in the RAW264.7 mouse macrophage cell line. Conclusions This is the first report that a marine bioproduct protects against experimental UC via the inhibition of both inflammation and apoptosis, very similar to the standard-of-care sulfasalazine, a well-known prodrug that releases 5-ASA. We believe that the oral administration of zonarol might offer a better treatment for human IBDs than 5-ASA, or may be useful as an alternative/additive therapeutic strategy against UC, without any evidence of side effects. PMID:25409433

Noguchi, Hirotsugu; Ueda, Yuki; Kitsuyama, Ryo; Shimizu, Hiroya; Tanimoto, Akihide; Wang, Ke-Yong; Nawata, Aya; Nakayama, Toshiyuki; Sasaguri, Yasuyuki; Satoh, Takumi

2014-01-01

141

21 CFR 201.22 - Prescription drugs containing sulfites; required warning statements.  

Code of Federal Regulations, 2013 CFR

...added to certain drug products to inhibit the oxidation of the active drug ingredient. Oxidation of the active drug ingredient may result...Examples of specific sulfites used to inhibit this oxidation process include sodium bisulfite,...

2013-04-01

142

Exposure of RML scrapie agent to a sodium percarbonate-based product and sodium dodecyl sulfate renders PrPSc protease sensitive but does not eliminate infectivity  

PubMed Central

Background Prions, the causative agents of the transmissible spongiform encephalopathies, are notoriously difficult to inactivate. Current decontamination recommendations by the World Health Organization include prolonged exposure to 1 N sodium hydroxide or?>?20,000 ppm sodium hypochlorite, or autoclaving. For decontamination of large stainless steel surfaces and equipment as in abattoirs, for example, these methods are harsh or unsuitable. The current study was designed to evaluate the effectiveness of a commercial product containing sodium percarbonate to inactivate prions. Samples of mouse brain infected with a mouse-adapted strain of the scrapie agent (RML) were exposed to a sodium percarbonate-based product (SPC-P). Treated samples were evaluated for abnormal prion protein (PrPSc)-immunoreactivity by western blot analysis, and residual infectivity by mouse bioassay. Results Exposure to a 21% solution of SPC-P or a solution containing either 2.1% or 21% SPC-P in combination with sodium dodecyl sulfate (SDS) resulted in increased proteinase K sensitivity of PrPSc. Limited reductions in infectivity were observed depending on treatment condition. A marginal effect on infectivity was observed with SPC-P alone, but an approximate 2–3 log10 reduction was observed with the addition of SDS, though exposure to SDS alone resulted in an approximate 2 log10 reduction. Conclusions This study demonstrates that exposure of a mouse-adapted scrapie strain to SPC-P does not eliminate infectivity, but does render PrPSc protease sensitive. PMID:23311930

2013-01-01

143

A study of the structure of mixed micellar solutions based on heptaethylene glycol monotetradecyl ether and sodium (lithium) dodecyl sulfate by the small-angle neutron scattering method  

SciTech Connect

The micellization in mixed aqueous systems based on a new nonionic surfactant, namely, heptaethylene glycol monotetradecyl ether (C{sub 14}E{sub 7}), and an anionic surfactant, namely, sodium dodecyl sulfate, sodium decyl sulfate, or lithium dodecyl sulfate, is studied by small-angle neutron scattering. Preliminary results of the investigation into the behavior of C{sub 14}E{sub 7} aqueous solutions (at two concentrations, 0.17 and 0.50%) upon addition of small amounts of three different classical anionic surfactants are reported.

Rajewska, A. [Joint Institute for Nuclear Research (Russian Federation)], E-mail: aldonar@jinr.ru; Medrzycka, K.; Hallmann, E. [Gdansk University of Technology (Poland)

2007-09-15

144

Structural analysis of protein complexes with sodium alkyl sulfates by small-angle scattering and polyacrylamide gel electrophoresis.  

PubMed

Small-angle X-ray (SAXS) and neutron (SANS) scattering is used to probe the structure of protein-surfactant complexes in solution and to correlate this information with their performance in gel electrophoresis. Proteins with sizes between 6.5 to 116 kDa are denatured with sodium alkyl sulfates (SC(x)S) of variable tail lengths. Several combinations of proteins and surfactants are analyzed to measure micelle radii, the distance between micelles, the extension of the complex, the radius of gyration, and the electrophoretic mobility. The structural characterization shows that most protein-surfactant complexes can be accurately described as pearl-necklace structures with spherical micelles. However, protein complexes with short surfactants (SC(8)S) bind with micelles that deviate significantly from spherical shape. Sodium decyl (SC(10)S) and dodecyl (SC(12)S, more commonly abbreviated as SDS) sulfates result in the best protein separations in standard gel electrophoresis. Particularly, SC(10)S shows higher resolutions for complexes of low molecular weight. The systematic characterization of alkyl sulfate surfactants demonstrates that changes in the chain architecture can significantly affect electrophoretic migration so that protein-surfactant structures could be optimized for high resolution protein separations. PMID:21182321

Ospinal-Jiménez, Mónica; Pozzo, Danilo C

2011-02-01

145

Therapeutic effect of a hydroxynaphthoquinone fraction on dextran sulfate sodium-induced ulcerative colitis  

PubMed Central

AIM: To evaluate the therapeutic effect of hydroxynaphthoquinone mixture (HM) on dextran sulfate sodium (DSS)-induced colitis and explore the underlying mechanisms. METHODS: BALB/c mice received 3.5% DSS for 6 d to induce ulcerative colitis. Groups of mice were orally administered HM 3.5, 7 and 14 mg/kg and mesalazine 200 mg/kg per day for 7 d. During the experiment, clinical signs and body weight, stool consistency and visible fecal blood were monitored and recorded daily. A disease activity index score was calculated for each animal. At the conclusion of the experiment, the colonic histopathological lesions were evaluated. Myeloperoxidase (MPO) activity and tumor necrosis factor-? (TNF-?) levels were determined. Protein expression levels of TNF-?, nuclear factor-?B (NF-?B) p65, inhibitor of ?B (I?B) and phosphorylation of I?B (p-I?B) were analyzed by Western blot analysis. RESULTS: Administration of 3.5% DSS for 6 d successfully induced acute colitis associated with soft stool, diarrhea, rectal bleeding, and colon shortening, as well as a loss of body weight. Administration of HM effectively attenuated the severity of colonic mucosa injury. For histopathological analysis, HM treatment improved histological alterations and lowered pathological scores compared with the DSS only group. This manifested as a reduction in the extent of colon injury and inflammatory cell infiltration, as well as the degree of mucosal destruction. In addition, HM at doses of 7 and 14 mg/kg significantly decreased MPO activity in colonic tissue (0.98 ± 0.22 U/g vs 1.32 ± 0.24 U/g, 0.89 ± 0.37 U/g vs 1.32 ± 0.24 U/g tissue, P < 0.05) and serum TNF-? levels (68.78 ± 7.34 ng/L vs 88.98 ± 17.79 ng/L, 64.13 ± 14.13 ng/L vs 88.98 ± 17.79 ng/L, P < 0.05). Furthermore, HM down-regulated the expression of TNF-?, NF-?B p65 and p-I?B? in colonic tissue while up-regulating I?B? protein expression. These results suggest that the significant anti-inflammatory effect of HM may be attributable to its inhibition of TNF-? production and NF-?B activation. CONCLUSION: HM had a favorable therapeutic effect on DSS-induced ulcerative colitis, supporting its further development and clinical application in inflammatory bowel disease. PMID:25386079

Zhang, Zi-Liang; Fan, Hua-Ying; Yang, Ming-Yan; Zhang, Zuo-Kai; Liu, Ke

2014-01-01

146

Investigations on interactions of sodium dodecyl sulfate and polyacryloamide molecules on calcium carbonate surface using radiotracer technique  

SciTech Connect

From the studies of sodium dodecyl sulfate (SDS) adsorption on nonflocculated and flocculated CaCO/sub 3/ precipitate it was found that on a CaCO/sub 3/ surface on which a polymer (polyacryloamide (PAA)) was previously adsorbed PAA and SDS complexes were formed. Studies of adsorption carried out on the function of the surface charge, SDS concentration, as well as flocculant concentration allowed a probable mechanism of SDS binding on flocculated CaCO/sub 3/ precipitate to be defined. In these studies a radiotracer technique was applied using SDS labeled with radioactive /sup 35/S for measurements of adsorption. 19 references.

Chibowski, S.

1980-08-01

147

Media-dependent antagonism of gentamicin sulfate by Liquoid (sodium polyanetholsulfonate)  

Microsoft Academic Search

Zusammenfassung Liquoid® wirkt als Antagonist zu Gentamicin-Sulfat in Abhängigkeit vom jeweiligen Testnährmedium. Zugabe von frischem Serum bedingt im Gegensatz zu Polymyxin B keine Verstärkung seiner antagonistischen Wirkung gegen Aminoglykosid-Antibiotika.

W. H. Traub; B. L. Lowrance

1969-01-01

148

Binary mixed micelles of chiral sodium undecenyl leucinate and achiral sodium undecenyl sulfate: I. Characterization and application as pseudostationary phases in micellar electrokinetic chromatography.  

PubMed

Sodium 10-undecenyl sulfate (SUS), sodium 10-undecenyl leucinate (SUL) and their five different mixed micelles at varied percent mole ratios were prepared. The critical micelle concentration (CMC), C(20), gamma(CMC), partial specific volume, methylene group selectivity, mobilities and elution window were determined using a variety of analytical techniques. These surfactant systems were then evaluated as novel pseudostationary phases in micellar electrokinetic chromatography (MEKC). As a commonly used pseudostationary phase in MEKC, sodium dodecyl sulfate (SDS) was also evaluated. The CMC values of SUS and SUL were found to be 26 and 16 mM, respectively, whereas the CMC of mixed surfactants was found to be very similar to that of SUL. The C(20) values decreased dramatically as the concentration of SUL is increased in the mixed micelle. An increase in SUL content gradually increased the methylene group selectivity making the binary mixed surfactants more hydrophobic. Linear solvation energy relationships (LSERs) and free energy of transfer studies were also applied to predict the selectivity differences between the surfactant systems. The cohesiveness and the hydrogen bond acidic character of the surfactant systems were found to have the most significant influence on selectivity and MEKC retention. The SUS and SDS showed the strongest while SUL showed the weakest hydrogen bond donating capacity. The basicity, interaction with n and pi-electrons of the solute and dipolarity/polarizability were the least significant factors in LSER model for the surfactant systems studied. Free energies of transfer of selected functional groups in each surfactant systems were also calculated and found to be in good agreement with the LSER data. PMID:19942224

Ahlstrom, David M; Hoyos, Yatzka M; Arslan, Hakan; Akbay, Cevdet

2010-01-15

149

Impairment in Sulfite Reductase Leads to Early Leaf Senescence in Tomato Plants1[W][OPEN  

PubMed Central

Sulfite reductase (SiR) is an essential enzyme of the sulfate assimilation reductive pathway, which catalyzes the reduction of sulfite to sulfide. Here, we show that tomato (Solanum lycopersicum) plants with impaired SiR expression due to RNA interference (SIR Ri) developed early leaf senescence. The visual chlorophyll degradation in leaves of SIR Ri mutants was accompanied by a reduction of maximal quantum yield, as well as accumulation of hydrogen peroxide and malondialdehyde, a product of lipid peroxidation. Interestingly, messenger RNA transcripts and proteins involved in chlorophyll breakdown in the chloroplasts were found to be enhanced in the mutants, while transcripts and their plastidic proteins, functioning in photosystem II, were reduced in these mutants compared with wild-type leaves. As a consequence of SiR impairment, the levels of sulfite, sulfate, and thiosulfate were higher and glutathione levels were lower compared with the wild type. Unexpectedly, in a futile attempt to compensate for the low glutathione, the activity of adenosine-5?-phosphosulfate reductase was enhanced, leading to further sulfite accumulation in SIR Ri plants. Increased sulfite oxidation to sulfate and incorporation of sulfite into sulfoquinovosyl diacylglycerols were not sufficient to maintain low basal sulfite levels, resulting in accumulative leaf damage in mutant leaves. Our results indicate that, in addition to its biosynthetic role, SiR plays an important role in prevention of premature senescence. The higher sulfite is likely the main reason for the initiation of chlorophyll degradation, while the lower glutathione as well as the higher hydrogen peroxide and malondialdehyde additionally contribute to premature senescence in mutant leaves. PMID:24987017

Yarmolinsky, Dmitry; Brychkova, Galina; Kurmanbayeva, Assylay; Bekturova, Aizat; Ventura, Yvonne; Khozin-Goldberg, Inna; Eppel, Amir; Fluhr, Robert; Sagi, Moshe

2014-01-01

150

Molecular interactions of sodium laureth sulfate with N-alkyl-1,3-propanediamine in aqueous solutions, based on potentiometric and photometric data  

NASA Astrophysics Data System (ADS)

The role of Coulomb and hydrophobic interactions in association and aggregation in binary solutions of anionic surfactant sodium laureth sulfate and cationic surfactant N-alkyl-1,3-propanediamine is established from the concentration dependences of the pH of the solutions. It is shown that the development of the processes is initiated by the Coulomb interaction of oppositely charged sodium laureth sulfate and N-alkyl-1,3-propanediamine molecules and enhanced by the hydrophobic interaction between the hydrocarbon tails of neutral associates of the surfactant molecules.

Yaremko, Z. M.; Fedushinskaya, L. B.; Burka, O. A.; Soltys, M. N.

2014-02-01

151

Formation of reactive sulfite-derived free radicals by the activation of human neutrophils: an ESR study.  

PubMed

The objective of this study was to determine the effect of (bi)sulfite (hydrated sulfur dioxide) on human neutrophils and the ability of these immune cells to produce reactive free radicals due to (bi)sulfite oxidation. Myeloperoxidase (MPO) is an abundant heme protein in neutrophils that catalyzes the formation of cytotoxic oxidants implicated in asthma and inflammatory disorders. In this study sulfite ((•)SO(3)(-)) and sulfate (SO(4)(•-)) anion radicals are characterized with the ESR spin-trapping technique using 5,5-dimethyl-1-pyrroline N-oxide (DMPO) in the reaction of (bi)sulfite oxidation by human MPO and human neutrophils via sulfite radical chain reaction chemistry. After treatment with (bi)sulfite, phorbol 12-myristate 13-acetate-stimulated neutrophils produced DMPO-sulfite anion radical, -superoxide, and -hydroxyl radical adducts. The last adduct probably resulted, in part, from the conversion of DMPO-sulfate to DMPO-hydroxyl radical adduct via a nucleophilic substitution reaction of the radical adduct. This anion radical (SO(4)(•-)) is highly reactive and, presumably, can oxidize target proteins to protein radicals, thereby initiating protein oxidation. Therefore, we propose that the potential toxicity of (bi)sulfite during pulmonary inflammation or lung-associated diseases such as asthma may be related to free radical formation. PMID:22326772

Ranguelova, Kalina; Rice, Annette B; Khajo, Abdelahad; Triquigneaux, Mathilde; Garantziotis, Stavros; Magliozzo, Richard S; Mason, Ronald P

2012-04-15

152

Microscopic evidence of "necklace and bead"-like morphology of polymer-surfactant complexes: a comparative study on poly(vinylpyrrolidone)-sodium dodecyl sulfate and poly(diallyldimethylammonium chloride)-sodium dodecyl sulfate systems.  

PubMed

Here, we report the microscopic evidence of "necklace and bead"-like morphology, which has long been the most widely accepted model for polymer-surfactant complexes. The lack of microscopic evidence of the initial complexation between surfactant and polymer has resulted in many contradictory reports in the literature. In this paper, we visualized these initial complexes formed between negatively charged surfactant sodium dodecyl sulfate (SDS) with neutral poly(vinylpyrrolidone) (PVP) and cationic poly(diallyldimethylammonium chloride) (PDADMAC) polymer through photoluminescence (PL) microscopy and atomic force microscopy (AFM) using silicon quantum dot (Si QD) as an external PL marker. It is observed that, for the PVP-SDS system, SDS molecules bind at the hydrophobic sites on the random-coiled PVP chain through their hydrocarbon tails, while for the PDADMAC-SDS system, SDS head groups are associated with the positively charged nitrogen centers of the polymer, where the polymer chain wraps around the surfactant head groups. PMID:25105837

Chatterjee, Surajit; Prajapati, Roopali; Bhattacharya, Arpan; Mukherjee, Tushar K

2014-08-19

153

Stopped-flow kinetic studies of sphere-to-rod transitions of sodium alkyl sulfate micelles induced by hydrotropic salt.  

PubMed

The kinetics and mechanism of sphere-to-rod transitions of sodium alkyl sulfate micelles induced by hydrotropic salt, p-toluidine hydrochloride (PTHC), were investigated by stopped-flow with light scattering detection. Spherical sodium dodecyl sulfate (SDS) micelles transform into short ellipsoidal shapes at low salt concentrations ([PTHC]/[SDS], chi(PTHC)=0.3 and 0.4). Upon stopped-flow mixing aqueous solutions of spherical SDS micelles with PTHC, the scattered light intensity gradually increases with time. Single exponential fitting of the dynamic traces leads to characteristic relaxation time, tau(g), for the growth process from spherical to ellipsoidal micelles, and it increases with increasing SDS concentrations. This suggests that ellipsoidal micelles might be produced by successive insertion of unimers into spherical micelles, similar to the case of formation of spherical micelles as suggested by Aniansson-Wall (A-W) theory. At chi(PTHC) > or = 0.5, rod-like micelles with much higher axial ratio form. The scattered light intensity exhibits an initially abrupt increase and then levels off. The dynamic curves can be well fitted with single exponential functions, and the obtained tau(g) decreases with increasing SDS concentration. Thus, the growth from spherical to rod-like micelles might proceed via fusion of spherical micelles, in agreement with mechanism proposed by Ikeda et al. At chi(PTHC)=0.3 and 0.6, the apparent activation energies obtained from temperature dependent kinetic studies for the micellar growth are 40.4 and 3.6 kJ/mol, respectively. The large differences between activation energies for the growth from spherical to ellipsoidal micelles at low chi(PTHC) and the sphere-to-rod transition at high chi(PTHC) further indicate that they should follow different mechanisms. Moreover, the sphere-to-rod transition kinetics of sodium alkyl sulfate with varying hydrophobic chain lengths (n=10, 12, 14, and 16) are also studied. The longer the carbon chain lengths, the slower the sphere-to-rod transition. PMID:17904570

Zhang, Jingyan; Ge, Zhishen; Jiang, Xiaoze; Hassan, P A; Liu, Shiyong

2007-12-15

154

Inhibition of superoxide dismutase, Vitamin C and glutathione on chemiluminescence produced by luminol and the mixture of sulfite and bisulfite  

NASA Astrophysics Data System (ADS)

In a system which consisted of luminol (3-aminophthalhydrazide), cobalt sulfate (CoSO 4), alkaline buffer and the mixture of NaSO 3 and sodium bisulfite (NaHSO 3) (sulfite and bisulfite = 3:1, m/m), a strong chemiluminescence (CL) was observed using a BPCL ultra-weak luminometer. The CL signals resulted from 3-aminophthalate (the product of oxidized luminol), and were affected by the buffer pH, buffer medium and the concentrations of luminol, CoSO 4 and the NaSO 3-NaHSO 3 mixture. The observation that the CL intensities were inhibited by superoxide dismutase (SOD), Vitamin C (Vc) and glutathione (GSH) in a dose-dependent manner suggested that superoxide radical (O 2rad -) was involved in the CL reaction and responsible for oxidation of luminol.

Geng, Hong; Meng, Ziqiang

2006-05-01

155

Phase Behavior of Microemulsions Formulated with Sodium Alkyl Polypropylene Oxide Sulfate and a Cationic Hydrotrope  

Microsoft Academic Search

The partial ternary phase diagram of anionic extended surfactant of alkyl polypropylene oxide sulfate C12(PO)4SO4 alone and combined with the cationic hydrotrope, tetrabutyl ammonium bromide with water and decane were determined under ambient conditions. Middle phase microemulsion was formulated using salinity scans in the dilute region of surfactant\\/brine\\/decane.Visual inspection as well as cross polarizer and optical microscopy were used to

Ibrahim Kayali; Khawla Qamhieh; Fuad Habjoqa; Abeer AlBawab; Ulf Olsson; Lada Bemert; Reinhard Strey

2011-01-01

156

Phase Behavior of Microemulsions Formulated with Sodium Alkyl Polypropylene Oxide Sulfate and a Cationic Hydrotrope  

Microsoft Academic Search

The partial ternary phase diagram of anionic extended surfactant of alkyl polypropylene oxide sulfate C12(PO)4SO4 alone and combined with the cationic hydrotrope, tetrabutyl ammonium bromide with water and decane were determined under ambient conditions. Middle phase microemulsion was formulated using salinity scans in the dilute region of surfactant\\/brine\\/decane. Visual inspection as well as cross polarizer and optical microscopy were used

Ibrahim Kayali; Khawla Qamhieh; Fuad Habjoqa; Abeer AlBawab; Ulf Olsson; Lada Bemert; Reinhard Strey

2012-01-01

157

Interaction of poly(oxyethylene glycol) with cyclohexane-pentanol-sodium dodecyl sulfate water-in-oil microemulsions  

SciTech Connect

The interaction of poly(oxyethylene glycol) (MW 6000) with cyclohexane/1-pentanol/sodium dodecyl sulfate microemulsions was studied with dynamic light scattering and luminescence probing techniques. Some conductivity measurements have also been made. Particular weight has been given to luminescence. The authors have chosen to analyze luminescence decay profiles by using models obtained from the theory of random walk in fractal domains, in order to deal with percolation phenomena present in the above system and to underline new information obtained by fractal models. Ru(Bpy){sub 3}{sup 2+} has been used as the lumophore and Fe(CN){sub 6}{sup 3-} as the quencher. It was found that the polymer induces a structural reorganization of the dispersed phase so that the aggregates grow in size. The geometry of the dispersed phase becomes more restricted in the presence of polymer and the quenching efficiency decreases. The electric conductivity undergoes a limited decrease. 42 refs., 8 figs., 4 tabs.

Lianos, P.; Modes, S.; Staikos, G. [Univ. of Patras (Greece)] [and others

1992-04-01

158

Effect of salt on the phase behavior of the ternary system water-phenol-sodium dodecyl sulfate  

SciTech Connect

A detailed study of the effects of varying temperature and salt concentration on the phase behavior of the water-pentanol-sodium dodecyl sulfate (SDS) system is presented. By addition of salt the lamellar phase extends well into the water-rich region and occurs at water contents exceeding 95%. The isotropic mixtures close in composition to the more dilute lamellar phase strongly scatter light and exhibit streaming birefringence. It seems that the isotropic-lamellar phase transition becomes less first order as the salt content increases. Moreover, this work provides evidence that in the water (salt)-pentanol-SDS system two mechanisms are involved to produce three-phase equilibria. Indeed, the authors results clearly show that three-phase regions arise from either a critical end point or an indifferent state.

Guerin, G.; Bellocq, A.M.

1988-05-05

159

The effect of caffeine on the reactions of the excited singlet state of pyrene in micellar sodium lauryl sulfate  

NASA Astrophysics Data System (ADS)

The effect of caffeine on a few photo-induced reactions of pyrene in micellar sodium lauryl sulfate (NaLS) has been studied. In these systems caffeine complexes with the pyrene (K asso = 85 ± 10 M -1 and also with the other reactants, e.g. Cu 2+ or TI +. The efficiencies of reactions which involve contact, i.e. pyrene excimer formation, and quenching by TI + ions to give the triplet state of pyrene, are significantly reduced in the presence of caffeine, due to geometric inhibitions formed by the complexation processes. The kinetics of photo-induced electron transfer, e.g. between excited pyrene and Cu 2+, are not affected. However, the subsequent reactions of the products are modified and the yield of ionic products is markedly increased.

Hashimoto, Shuichi; Thomas, J. Kerry

1984-08-01

160

Influence of Sodium Lauryl Sulfate and Tween 80 on Carbamazepine-Nicotinamide Cocrystal Solubility and Dissolution Behaviour  

PubMed Central

The influence of the surfactants of sodium lauryl sulfate (SLS) and Tween 80 on carbamazepine–nicotinamide (CBZ–NIC) cocrystal solubility and dissolution behaviour has been studied in this work. The solubility of the CBZ–NIC cocrystal was determined by measuring the eutectic concentrations of the drug and the coformer. Evolution of the intrinsic dissolution rate (IDR) of the CBZ–NIC cocrystal was monitored by the UV imaging dissolution system during dissolution. Experimental results indicated that SLS and Tween 80 had little influence upon the solubility of the CBZ–NIC cocrystal but they had totally opposite effects on the IDR of the CBZ–NIC cocrystal during dissolution. SLS significantly increased the IDR of the CBZ–NIC cocrystal while Tween 80 decreased its IDR. PMID:24300560

Li, Mingzhong; Qiao, Ning; Wang, Ke

2013-01-01

161

Comparative study of photoluminescence of single-walled carbon nanotubes wrapped with sodium dodecyl sulfate, surfactin and polyvinylpyrrolidone  

NASA Astrophysics Data System (ADS)

Single-walled carbon nanotubes (SWCNTs) have been dispersed with three types of amphiphilic materials in aqueous solutions: (i) an anionic aliphatic surfactant, sodium dodecyl sulfate (SDS), (ii) a cyclic lipopeptide biosurfactant, surfactin, and (iii) a water-soluble polymer, polyvinylpyrrolidone (PVP). Solution photoluminescence (PL) studies suggest that SDS wrapping is very sensitive to the temperature whereas the other two give relatively robust wrapping around the SWCNTs. Low temperature PL spectra from both surfactin and PVP dispersed SWCNTs show that peak shifts are strongly dependent on their chiralities, which can be explained by the bandgap modulations with the environmental strain. The uniaxial and torsional strains deduced from their bandgap shifts were similar, indicating the strains are mainly due to the different rates of thermal expansion in SWCNTs and ice.

Li, Lain-Jong; Nicholas, R. J.; Chen, Chien-Yen; Darton, R. C.; Baker, S. C.

2005-05-01

162

DISSOLUTION AND CRYSTALLIZATION OF CALCIUM SULFITE PLATELETS  

EPA Science Inventory

The paper discusses the dissolution and crystallization of calcium sulfite platelets. The rates of calcium sulfite dissolution and crystallization are important in slurry scrubbing processes for flue gas desulfurization. The rates affect the scrubber solution composition, SO2 abs...

163

Skin Barrier Disruption by Sodium Lauryl Sulfate-Exposure Alters the Expressions of Involucrin, Transglutaminase 1, Profilaggrin, and Kallikreins during the Repair Phase in Human Skin In Vivo  

Microsoft Academic Search

Detergents are skin irritants affecting keratinocytes. In this study, healthy volunteers were exposed to water (vehicle) and 1% sodium lauryl sulfate (SLS) under occlusive patch tests for 24 hours. The messenger RNA (mRNA) expression of keratinocyte differentiation markers and of enzymes involved in corneodesmosome degradation was examined in skin biopsies (n=8) during the repair phase (6 hours to 7 days

Hans Törmä; Magnus Lindberg; Berit Berne

2008-01-01

164

Rumen enzyme profile and fermentation characteristics in sheep as affected by treatment with sodium lauryl sulfate as defaunating agent and presence of ciliate protozoa  

Microsoft Academic Search

The efficiency of sodium lauryl sulfate as a defaunating agent and effect of rumen protozoa on nutrient utilization, fermentation characteristics and enzyme profile were evaluated in adult sheep maintained on a mixed ration containing 65:35% Pala (Ziziphus numularia) leaf: concentrate. Twenty-one adult Malpura sheep divided into three equal groups (DF, RF and F) were either defaunated by oral administration of

A. Santra; S. A. Karim; O. H. Chaturvedi

2007-01-01

165

Determination of anabolic steroids in pharmaceuticals by liquid chromatography with a microemulsion of sodium dodecyl sulfate and pentanol as mobile phase  

Microsoft Academic Search

The Chromatographic behaviour of fourteen anabolic steroids using micellar mobile phases has been studied. Anabolic steroids are strongly associated with the non-modified alkyl chains of the C18 stationary phase. However, appropriate retention times were obtained with a microemulsion of 0.1 M sodium dodecyl sulfate (SDS) and 7% pentanol as mobile phase (capacity factors, k? < 14). A Chromatographic procedure for

S. Torres Cartas; M. C. García Alvarez-Coque; R. M. Villanueva Camañas

1995-01-01

166

Interference in the Coomassie Brilliant Blue and Pyrogallol Red protein dye-binding assays is increased by the addition of sodium dodecyl sulfate to the dye reagents  

Microsoft Academic Search

We have investigated the effect of sodium dodecyl sulfate (SDS) upon the response of the Coomassie Brilliant Blue (CBB) and Pyrogallol Red-molybdate (PRM) protein dye-binding assays to interference from aminoglycosides, ampholytes, detergents, phenothiazines, reducing agents, and miscellaneous substances previously reported to interfere with the assays. The CBB assay was less prone to interference than the PRM assay but gave positive

Thomas Marshall; Katherine M Williams

2004-01-01

167

Combined intravesical sodium hyaluronate/chondroitin sulfate therapy for interstitial cystitis/bladder pain syndrome: a prospective study  

PubMed Central

Objectives: The aim of this study was to verify the efficacy and safety of intravesical treatment combining sodium hyaluronate (HA) and chondroitin sulfate (CS) in patients with interstitial cystitis/bladder pain syndrome (IC/BPS). Methods: Between February 2010 and May 2011, 20 consecutive women with IC/BPS were treated with intravesical instillations containing sodium HA (1.6%; 800 mg/50 ml) and sodium CS (2%; 1 g/50 ml) weekly for the first month, biweekly for the second month, and then monthly for at least 3 months. Before and after treatment, all patients filled in the Interstitial Cystitis Symptom Index and Problem Index (ICSI/ICPI), the Patient Health Questionnaire 9 and the Pelvic Pain and Urgency/Frequency Patient Symptom Scale (PUF). Treatment efficacy was assessed by comparing the pre- and post-treatment mean scores of the three questionnaires using Student’s t test (p value <0.05 was considered significant). Results: Statistically significant mean decreases in ICSI (from 13.0 to 9.3; p = 0.0003), ICPI (from 11.35 to 8.85; p = 0.0078) and PUF (from 20.0 to 15.75; p = 0.0007) questionnaire scores were seen. No cases of side effects or complications were observed. The mean follow up was 5 months. Conclusions: Despite the limitations of this study, the outcomes confirmed the role of combination therapy with HA and CS as a safe and effective option for the treatment of IC/BPS. Further randomized controlled studies with a higher number of patients and a longer follow-up period are needed to confirm these results. PMID:23904856

Giberti, Claudio; Cortese, Pierluigi; Schenone, Maurizio

2013-01-01

168

Adhesion of sodium dodecyl sulfate surfactant monolayers with TiO2 (rutile and anatase) surfaces  

SciTech Connect

Surfactants are widely used as templates to control the nucleation and growth of nanostructured metal oxides such as titania. To gain insight into the origin of surfactant-titania interactions responsible for polymorph and orientation selection, we simulate the self-assembly of an anionic surfactant monolayer on various low-index titania surfaces and for a range of densities. We characterize the binding in each case and compute the adhesion energies, finding anatase (100) and rutile (110) to be the strongest-binding surfaces. The sodium counterions in the monolayer are found to dominate the adhesion. It is also observed that the assembly is directed predominantly by surface-monolayer electrostatic complementarity.

Darkins, Robert; Sushko, Maria L.; Liu, Jun; Duffy, Dorothy M.

2013-09-17

169

Sulfur isotope fractionation during bacterial reduction and disproportionation of thiosulfate and sulfite  

SciTech Connect

In bacterial cultures the authors measured sulfur isotope fractionation during transformations of thiosulfate and sulfite, pathways which may be of considerable importance in the cycling of sulfur in marine sediments and euxinic waters. They documented isotope fractionations during the reduction and disproportionation of thiosulfate and sulfite by bacterial enrichments and pure bacterial cultures from marine and freshwater environments. They also measured the isotope fractionation associated with the anoxygenic phototrophic oxidation of H{sub 2}S to thiosulfate by cyanobacteria. Except for sulfite reduction, isotope fractionations for these processes have not been previously reported. During the dissimilatory reduction of sulfite, H{sub 2}S was depleted in {sup 34}S by 6%, and during the reduction of thiosulfate to H{sub 2}S, depletions were between 7% and 11%. The largest observed isotope fractionation was associated with the bacterial disproportionation of sulfite which caused a {sup 34}S depletion in H{sub 2}S of 20--37% and a {sup 34}S enrichment in sulfate of 7--12%. During the bacterial disproportionation of thiosulfate, isotope fractionations between the outer sulfane sulfur and H{sub 2}S and between the inner sulfonate sulfur and sulfate were <4%. The authors observed isotope exchange between the two sulfur atoms of thiosulfate leading to a depletion of {sup 34}S in H{sub 2}S by up to 12% with a comparable enrichment of {sup 34}S in sulfate. No isotope fractionation was associated with the anoxygenic phototrophic oxidation of H{sub 2}S to thiosulfate. The depletion of {sup 34}S into H{sub 2}S during the bacterial reduction and disproportionation of thiosulfate and sulfite may, in addition to sulfate reduction and the bacterial disproportionation of elemental sulfur, contribute to the generation of {sup 34}S-depleted sedimentary sulfides.

Habicht, K.S.; Canfield, D.E. [Max Planck Inst. for Marine Microbiology, Bremen (Germany)] [Max Planck Inst. for Marine Microbiology, Bremen (Germany); Rethmeier, J. [Bremen Univ. (Germany)] [Bremen Univ. (Germany)

1998-08-01

170

Cyclic voltammetric behavior of the lead electrode in sodium sulfate solutions  

NASA Astrophysics Data System (ADS)

Cyclic voltammograms (CVs) of the Pb electrode were obtained in Na 2SO 4 solutions as a function of starting potential, electrolyte concentration, voltage range and voltage scanning rate. The shape of the voltammograms was found to depend on the starting potential as well on the sweep number. This is probably due to changes in the activation state of the electrode surface. In the first sweep, the anodic portion of the voltammograms is characterized by a shoulder and three peaks as a result of the formation of PbSO 4, PbO, PbO 2 and transformation of PbSO 4 to PbO 2, respectively, on the electrode surface before the evolution of oxygen. On the other hand, in the second and later sweeps, an additional anodic peak appeared which may be due to the formation of intermediate oxides. The cathodic portion shows the occurrence of three peaks corresponding to the reduction of PbO 2 to PbSO 4, PbO 2 to PbO and the latter with PbSO 4 to spongy lead, respectively, followed by the formation of PbH 2 before evolution of hydrogen. A correlation was made between the anodic peaks and their corresponding cathodic ones. Increasing the sulfate anion concentration increased the highest of the peak currents and shifted the anodic peak potentials towards more negative values. A linear relationship was obtained between the logarithm of the anodic peak current densities and the logarithm of SO 42- anion concentration. An increase in the scan rate enhanced the current density of both the anodic and cathodic branches. Also, the anodic potentials are shifted towards more positive values, whereas the cathodic peaks are shifted in the negative direction, indicating irreversible formation of the passive film on the electrode surface.

Abd El Aal, E. E.

171

A dissimilatory sirohaem-sulfite-reductase-type protein from the hyperthermophilic archaeon Pyrobaculum islandicum.  

PubMed

A sulfite-reductase-type protein was purified from the hyperthermophilic crenarchaeote Pyrobaculum islandicum grown chemoorganoheterotrophically with thiosulfate as terminal electron acceptor. In common with dissimilatory sulfite reductases the protein has an alpha 2 beta 2 structure and contains high-spin sirohaem, non-haem iron and acid-labile sulfide. The oxidized protein exhibits absorption maxima at 280, 392, 578 and 710 nm with shoulders at 430 and 610 nm. The isoelectric point of pH 8.4 sets the protein apart from all dissimilatory sulfite reductases characterized thus far. The genes for the alpha- and beta-subunits (dsrA and dsrB) are contiguous in the order dsrAdsrB and most probably comprise an operon with the directly following dsrG and dsrC genes. dsrG and dsrC encode products which are homologous to eukaryotic glutathione S-transferases and the proposed gamma-subunit of Desulfovibrio vulgaris sulfite reductase, respectively. dsrA and dsrB encode 44.2 kDa and 41.2 kDa peptides which show significant similarity to the two homologous subunits DsrA and DsrB of dissimilatory sulfite reductases. Phylogenetic analyses indicate a common protogenotic origin of the P. islandicum protein and the dissimilatory sulfite reductases from sulfate-reducing and sulfide-oxidizing prokaryotes. However, the protein from P. islandicum and the sulfite reductases from sulfate-reducers and from sulfur-oxidizers most probably evolved into three independent lineages prior to divergence of archaea and bacteria. PMID:9493389

Molitor, M; Dahl, C; Molitor, I; Schäfer, U; Speich, N; Huber, R; Deutzmann, R; Trüper, H G

1998-02-01

172

Monocolonization of Germ-Free Mice with Bacteroides fragilis Protects against Dextran Sulfate Sodium-Induced Acute Colitis  

PubMed Central

Ulcerative colitis is inflammatory conditions of the colon caused by interplay of genetic and environmental factors. Previous studies indicated that the gut microflora may be involved in the colonic inflammation. Bacteroides fragilis (BF) is a Gram-negative anaerobe belonging to the colonic symbiotic. We aimed to investigate the protective role of BF in a colitis model induced in germ-free (GF) mice by dextran sulfate sodium (DSS). GF C57BL/6JNarl mice were colonized with BF for 28 days before acute colitis was induced by DSS. BF colonization significantly increased animal survival by 40%, with less reduction in colon length, and decreased infiltration of inflammatory cells (macrophages and neutrophils) in colon mucosa following challenge with DSS. In addition, BF could enhance the mRNA expression of anti-inflammatory-related cytokine such as interleukin 10 (IL-10) with polymorphism cytokine IL-17 and diminish that of proinflammatory-related tumor necrosis factor ? with inducible nitric oxide synthase in the ulcerated colon. Myeloperoxidase activity was also decreased in BF-DSS mice. Taking these together, the BF colonization significantly ameliorated DSS-induced colitis by suppressing the activity of inflammatory-related molecules and inducing the production of anti-inflammatory cytokines. BF may play an important role in maintaining intestinal immune system homeostasis and regulate inflammatory responses. PMID:24971344

Liu, Ju-Yun; Li, Yen-Peng; Huang, Yen-Te; Chuang, Hsiao-Li

2014-01-01

173

Small angle neutron scattering study of sodium dodecyl sulfate micellar growth driven by addition of a hydrotropic salt.  

PubMed

The structures of aggregates formed in aqueous solutions of an anionic surfactant, sodium dodecyl sulfate (SDS), with the addition of a cationic hydrotropic salt, p-toluidine hydrochloride (PTHC), have been investigated by small angle neutron scattering (SANS). The SANS spectra exhibit a pronounced peak at low salt concentration, indicating the presence of repulsive intermicellar interactions. Model-independent real space information about the structure is obtained from a generalized indirect Fourier transformation (GIFT) technique in combination with a suitable model for the interparticle structure factor. The interparticle interaction is captured using the rescaled mean spherical approximation (RMSA) closure relation and a Yukawa form of the interaction potential. Further quantification of the geometrical parameters of the micelles was achieved by a complete fit of the SANS data using a prolate ellipsoidal form factor and the RMSA structure factor. The present study shows that PTHC induces a decrease in the fractional charge of the micelles due to adsorption at the micellar surface and consequent growth of the SDS micelles from nearly globular to rodlike as the concentration of PTHC increases. PMID:16256467

Hassan, P A; Fritz, Gerhard; Kaler, Eric W

2003-01-01

174

Inhibition of ribonuclease. Efficacy of sodium dodecyl sulfate, diethyl pyrocarbonate, protein ase K and heparin using a sensitive ribonuclease assay.  

PubMed

The effectiveness of several commonly used inhibitors of ribonuclease (RNAase) has been studied using the removal of radio-labelled leucine from leucyl-tRNA as a sensitive assay for RNAase activity. The inhibitors were tested under a variety of conditions, varying the temperature, the pH, and the source of RNAase. When each inhibitor is udes separately in the presence of pancreatic RNAase, sodium dodecyl sulfate (SDS) is the most effective; but during long exposures to temperatures above 0 degrees C considerable amounts of RNA are still degraded. Combination of inhibitors are more effective in preserving RNA; with this assay, a combination of SDS with diethyl pyrocarbonate is the most effective. Proteinase K acts as an inhibitor when used in combination with SDS; however, it has RNAase activity when used by itself. Diethyl pyrocarbonate, when used at the high range of concentrations employed by others for RNAase inhibition, reacts with RNA changing its charge. However, when diethyl pyrocarbonate is used in smaller amounts the effects on RNA are minimal, and when used in combination with SDS it effectively inhibits RNAase. PMID:27220

Mendelsohn, S L; Young, D A

1978-07-24

175

Adsorption of mixtures of poly(amidoamine) dendrimers and sodium dodecyl sulfate at the air-water interface.  

PubMed

We relate the adsorption from mixtures of well-defined poly(amidoamine) (PAMAM) dendrimers of generations 4 and 8 with sodium dodecyl sulfate (SDS) at the air-water interface to the bulk solution properties. The anionic surfactant shows strong attractive interactions with the cationic dendrimers at pH 7, and electrophoretic mobility measurements indicate that the association is primarily driven by electrostatic interactions. Optical density measurements highlight the lack of colloidal stability of the formed bulk aggregates at compositions close to charge neutrality, the time scale of which is dependent on the dendrimer generation. Adsorption at the air-water interface was followed from samples immediately after mixing using a combination of surface tension, neutron reflectometry, and ellipsometry measurements. In the phase separation region for dendrimers of generation 4, we observed high surface tension corresponding to a depleted surfactant solution but only when the aggregates carried an excess of surfactant. Interestingly, these depleted adsorption layers contained spontaneously adsorbed macroscopic aggregates, and these embedded particles do not rearrange to spread monomeric material at the interface. These findings are discussed in relation to the interfacial properties of mixtures involving dendrimers of generation 8 as well as polydisperse linear and hyperbranched polyelectrolytes where there is polyelectrolyte bound to a surfactant monolayer. The results presented here demonstrate the capability of dendrimers to sequester anionic surfactants in a controllable manner, with potential applications as demulsification and antifoaming agents. PMID:24785641

Arteta, Marianna Yanez; Campbell, Richard A; Nylander, Tommy

2014-05-27

176

Molecular dynamics simulation of cetyltrimethylammonium bromide and sodium octyl sulfate mixtures: aggregate shape and local surfactant distribution.  

PubMed

To examine the self-assembly of cationic-anionic (catanionic) surfactant mixtures, we performed molecular dynamical (MD) simulations at fixed surfactant numbers but different ratios of cationic cetyltrimethylammonium bromide (CTAB) and anionic sodium octyl sulfate (SOS) aqueous mixtures, which were investigated previously (J. Phys. Chem. 1996, 100, 5874-5879). The simulation results show that with an increase of CTAB, there are two different potential aggregation evolving paths. For SOS-rich mixtures, the aggregation transition is sphere-disc-rod, while in CTAB-rich mixtures, it is rod-sphere. Furthermore, a disc micelle model was built to explain the shape of the aggregates with varying compositions of CTAB and SOS. In the model, the surfactant distribution in disc micelles is spontaneously adjusted according to the different curvature of the disc surface. The short-tailed SOS tends to stay in the edge region of high curvature, while in the disc center, where the curvature is very low, equimolar mixing of cationic and anionic surfactants is better for the arrangement of CTAB and SOS. Based on this model, the relation between the shape and composition of CTAB and SOS aggregates is well established by analyzing the local surfactant distribution. These new simulations on the evolving mechanism of aggregate shape are very important for the full understanding of the complex phase behavior in cationic and anionic mixtures and for the self-assembly of other mixed surfactant systems. PMID:23463240

Chen, Jingfei; Hao, Jingcheng

2013-04-21

177

Spontaneous transformations between surfactant bilayers of different topologies observed in mixtures of sodium octyl sulfate and hexadecyltrimethylammonium bromide.  

PubMed

The influence of adding salt on the self-assembly in sodium octyl sulfate (SOS)-rich mixtures of the anionic surfactant SOS and the cationic surfactant hexadecyltrimethylammonium bromide (CTAB) have been investigated with the two complementary techniques, small-angle neutron scattering (SANS) and cryo-transmission electron microscopy. We are able to conclude that addition of a substantial amount of inert salt, NaBr, mainly has three effects on the structural behaviors: (i) the micelles become much larger at the transition from micelles to bilayers, (ii) the fraction of bilayer disks increases at the expense of vesicles, and (iii) bilayer aggregates perforated with holes are formed in the most diluted samples. A novel form factor valid for perforated bilayer vesicles and disks is introduced for the first time and, as a result, we are able to directly observe the presence of perforated bilayers by means of fitting SANS data with an appropriate model. Moreover, we are able to conclude that the morphology of bilayer aggregates changes according to the following sequence of different bilayer topologies, vesicles ? disks ? perforated bilayers, as the electrolyte concentration is increased and surfactant mole fraction in the bilayer aggregates approaches equimolarity. We are able to rationalize this sequence of transitions as a result of a monotonous increase of the bilayer saddle-splay constant (k(c)(bi)) with decreasing influence from electrostatics, in agreement with theoretical predictions as deduced from the Poisson-Boltzmann theory. PMID:24697326

Bergström, L Magnus; Skoglund, Sara; Edwards, Katarina; Eriksson, Jonny; Grillo, Isabelle

2014-04-15

178

On-line isotachophoretic preconcentration and gel electrophoretic separation of sodium dodecyl sulfate-proteins on a microchip.  

PubMed

A microchip for integrated isotachophoretic (ITP) preconcentration with gel electrophoretic (GE) separation to decrease the detectable concentration of sodium dodecyl sulfate (SDS)-proteins was developed. Each channel of the chip was designed with a long sample injection channel to increase the sample loading and allow stacking the sample into a narrow zone using discontinuous ITP buffers. The pre-concentrated sample was separated in GE mode in sieving polymer solutions. All the analysis steps including injection, preconcentration, and separation of the ITP-GE process were performed continuously, controlled by a high-voltage power source with sequential voltage switching between the analysis steps. Without deteriorating the peak resolution, four SDS-protein analyses with integrated ITP-GE system resulted in a decreased detectable concentration of approximately 40-fold compared to the GE mode only. A good calibration curve for molecular weights of SDS-proteins indicated that the integrated ITP-GE system can be used for qualitative analysis of unknown protein samples. PMID:15852349

Huang, Huaiqing; Xu, Feng; Dai, Zhongpeng; Lin, Bingcheng

2005-06-01

179

Gradient polyacrylamide gel electrophoresis in presence of sodium dodecyl sulfate: a practical approach to muscle contractile and regulatory proteins.  

PubMed

Two gradient systems for polyacrylamide gel electrophoresis (PAGE) in the presence of sodium dodecyl sulfate (SDS) are described, with emphasis on improvements accumulated over two decades of studies on contractile proteins and regulatory enzymes from smooth muscle. The first "big slab" system utilizes 18 x 20 x 0.1 cm3 gels and a 10-18% acrylamide gradient, optimized for a high resolution of 10 to 500 kDa polypeptides. Eight (or more) gels are cast simultaneously with a gradient formation from "bottom to top" and 20% glycerol is added to the 18% acrylamide solution. The second "minislab" system represents an improved version of the system of Matsudaira and Burgess (Anal. Biochem. 1978, 87, 386-396), with 8 x 10 x 0.05 cm3 gels and 5-15% or 9-18% acrylamide gradient ranges. They are cast from "top to bottom" in 28-piece batches also with the addition of glycerol for improved gradient formation. Both types of gels can also be cast individually using a specially designed pestle-type gradient maker. For gel destaining, a convenient continuous hydrodynamic destainer is also described. PMID:7859701

Sobieszek, A

1994-01-01

180

Effect of topical laurocapram (Azone) on the in vitro percutaneous permeation of sodium lauryl sulfate using human skin.  

PubMed

The probability of simultaneous cutaneous exposure to surfactants and penetration enhancers could occur frequently during routine skin treatment. This study ascertains whether pre-exposure of skin to laurocapram would affect the penetration of a model surfactant, sodium lauryl sulfate (SLS). In vitro experiments with human skin were performed to compare the penetration of SLS after pretreatment with (1) different concentrations of laurocapram, (2) after repeated SLS treatments, (3) untreated controls, and (4) water-control. Pre-exposure to laurocapram enhanced penetration of SLS compared to all other treatments (p < 0.05). Since subsequent pre-exposure of skin to laurocapram increased SLS penetration, the chances of an elevated skin irritation reaction at the exposed site may therefore be possible. Pre-exposure of the skin with SLS did not increase the SLS flux values significantly, compared to the laurocapram pretreated skin. From these results it can be proposed that proper care and precautions may be necessary after exposure of skin to laurocapram and also to various other percutaneous enhancers. Further in vivo correlations are essential to define the clinical implications of this study, especially as related to irritant dermatitis. PMID:8800295

Szolar-Platzer, C; Patil, S; Maibach, H I

1996-05-01

181

Enhancing the transdermal delivery of rigid nanoparticles using the simultaneous application of ultrasound and sodium lauryl sulfate  

PubMed Central

The potential of rigid nanoparticles to serve as transdermal drug carriers can be greatly enhanced by improving their skin penetration. Therefore, the simultaneous application of ultrasound and sodium lauryl sulfate (referred to as US/SLS) was evaluated as a skin pre-treatment method for enhancing the passive transdermal delivery of nanoparticles. We utilized inductively-coupled plasma mass spectrometry and an improved application of confocal microscopy to compare the delivery of 10- and 20-nm cationic, neutral, and anionic quantum dots (QDs) into US/SLS-treated and untreated pig split-thickness skin. Our findings include: (a) ~0.01% of the QDs penetrate the dermis of untreated skin (which we quantify for the first time), (b) the QDs fully permeate US/SLS-treated skin, (c) the two cationic QDs studied exhibit different extents of skin penetration and dermal clearance, and (d) the QD skin penetration is heterogeneous. We discuss routes of nanoparticle skin penetration and the application of the methods described herein to address conflicting literature reports on nanoparticle skin penetration. We conclude that US/SLS treatment significantly enhances QD transdermal penetration by 500–1300%. Our findings suggest that an optimum surface charge exists for nanoparticle skin penetration, and motivate the application of nanoparticle carriers to US/SLS-treated skin for enhanced transdermal drug delivery. PMID:20971504

Lopez, Renata F.V.; Seto, Jennifer E.; Blankschtein, Daniel; Langer, Robert

2010-01-01

182

Enhancing the transdermal delivery of rigid nanoparticles using the simultaneous application of ultrasound and sodium lauryl sulfate.  

PubMed

The potential of rigid nanoparticles to serve as transdermal drug carriers can be greatly enhanced by improving their skin penetration. Therefore, the simultaneous application of ultrasound and sodium lauryl sulfate (referred to as US/SLS) was evaluated as a skin pre-treatment method for enhancing the passive transdermal delivery of nanoparticles. We utilized inductively coupled plasma mass spectrometry and an improved application of confocal microscopy to compare the delivery of 10- and 20-nm cationic, neutral, and anionic quantum dots (QDs) into US/SLS-treated and untreated pig split-thickness skin. Our findings include: (a) ?0.01% of the QDs penetrate the dermis of untreated skin (which we quantify for the first time), (b) the QDs fully permeate US/SLS-treated skin, (c) the two cationic QDs studied exhibit different extents of skin penetration and dermal clearance, and (d) the QD skin penetration is heterogeneous. We discuss routes of nanoparticle skin penetration and the application of the methods described herein to address conflicting literature reports on nanoparticle skin penetration. We conclude that US/SLS treatment significantly enhances QD transdermal penetration by 500-1300%. Our findings suggest that an optimum surface charge exists for nanoparticle skin penetration, and motivate the application of nanoparticle carriers to US/SLS-treated skin for enhanced transdermal drug delivery. PMID:20971504

Lopez, Renata F V; Seto, Jennifer E; Blankschtein, Daniel; Langer, Robert

2011-01-01

183

Determination of M/G ratio of propylene glycol alginate sodium sulfate by HPLC with pre-column derivatization.  

PubMed

A reliable high performance liquid chromatography with pre-column derivatization method was developed for the determination of the mannuronic acid (M)/guluronic acid (G) ratio of propylene glycol alginate sodium sulfate (PSS). The hydrolysis conditions of PSS were investigated by four degradation methods based on the degree of destruction of M and G, and the chromatographic separation conditions were also optimized. A satisfactory resolution of M and G was achieved with a KP-C18 column using 0.1 mol/L phosphate buffer (pH 7.0)-acetonitrile (83/17, v/v) as a mobile phase, after PSS was hydrolyzed with 0.1 mol/L sulfuric acid and labeled with 1-phenyl-3-methyl -5-pyrazolone. The M/G ratio of PSS determined by this method was in good accordance with that obtained by the (1)H NMR method with a desulfurization strategy. Our method is rapid, sensitive, accurate and reproducible. The limit of detection was found to be 0.25 ?g/mL for M and 0.40 ?g/mL for G. PMID:24607155

Wu, Jian; Zhao, Xia; Ren, Li; Xue, Yiting; Li, Chunxia; Yu, Guangli; Guan, Huashi

2014-04-15

184

Adsorption of hydroxamate siderophores and EDTA on goethite in the presence of the surfactant sodium dodecyl sulfate  

PubMed Central

Siderophore-promoted iron acquisition by microorganisms usually occurs in the presence of other organic molecules, including biosurfactants. We have investigated the influence of the anionic surfactant sodium dodecyl sulfate (SDS) on the adsorption of the siderophores DFOB (cationic) and DFOD (neutral) and the ligand EDTA (anionic) onto goethite (?-FeOOH) at pH 6. We also studied the adsorption of the corresponding 1:1 Fe(III)-ligand complexes, which are products of the dissolution process. Adsorption of the two free siderophores increased in a similar fashion with increasing SDS concentration, despite their difference in molecule charge. In contrast, SDS had little effect on the adsorption of EDTA. Adsorption of the Fe-DFOB and Fe-DFOD complexes also increased with increasing SDS concentrations, while adsorption of Fe-EDTA decreased. Our results suggest that hydrophobic interactions between adsorbed surfactants and siderophores are more important than electrostatic interactions. However, for strongly hydrophilic molecules, such as EDTA and its iron complex, the influence of SDS on their adsorption seems to depend on their tendency to form inner-sphere or outer-sphere surface complexes. Our results demonstrate that surfactants have a strong influence on the adsorption of siderophores to Fe oxides, which has important implications for siderophore-promoted dissolution of iron oxides and biological iron acquisition. PMID:19523232

2009-01-01

185

Pregnancy-specific glycoprotein 1 (PSG1) activates TGF-? and prevents dextran sodium sulfate (DSS)-induced colitis in mice.  

PubMed

Transforming growth factor-?s (TGF-?s) are secreted from cells as latent complexes and the activity of TGF-?s is controlled predominantly through activation of these complexes. Tolerance to the fetal allograft is essential for pregnancy success; TGF-?1 and TGF-?2 play important roles in regulating these processes. Pregnancy-specific ?-glycoproteins (PSGs) are present in the maternal circulation at a high concentration throughout pregnancy and have been proposed to have anti-inflammatory functions. We found that recombinant and native PSG1 activate TGF-?1 and TGF-?2 in vitro. Consistent with these findings, administration of PSG1 protected mice from dextran sodium sulfate (DSS)-induced colitis, reduced the secretion of pro-inflammatory cytokines, and increased the number of T regulatory cells. The PSG1-mediated protection was greatly inhibited by the coadministration of neutralizing anti-TGF-? antibody. Our results indicate that proteins secreted by the placenta directly contribute to the generation of active TGF-? and identify PSG1 as one of the few known biological activators of TGF-?2. PMID:23945545

Blois, S M; Sulkowski, G; Tirado-González, I; Warren, J; Freitag, N; Klapp, B F; Rifkin, D; Fuss, I; Strober, W; Dveksler, G S

2014-03-01

186

Multiscale molecular dynamics simulations of sodium dodecyl sulfate micelles: from coarse-grained to all-atom resolution.  

PubMed

Sodium dodecyl sulfate (SDS) is a well-known anionic detergent widely used in both experimental and theoretical investigations. Many molecular dynamics (MD) simulation have been performed on the SDS molecule at coarse-grained (CG), united-atom (UA), and all-atom (AA) resolutions. However, these simulations are usually based on general parameters determined from large sets of molecules, and as a result, peculiar molecular specificities are often poorly represented. In addition, the parameters (ideal bond lengths, angles, dihedrals and charge distribution) differ according to the resolution, highlighting a lack of coherence. We therefore propose a new set of parameters for CG, UA, and AA resolutions based on a high quantum mechanics (QM) level optimization of the detergent structure and the charge distribution. For the first time, QM-optimized parameters were directly applied to build the AA, UA, and CG model of the SDS molecule, leading to a more coherent description. As a test case, MD simulations were then performed on SDS preformed micelles as previous experimental and theoretical investigations allow direct comparison with our new sets of parameters. While all three models yield similar macromolecular properties (size, shape, and accessible surface) perfectly matching previous results, the attribution of more coherent parameters to SDS enables the description of the specific interactions inside and outside the micelle. These more consistent parameters can now be used to accurately describe new multi-scale systems involving the SDS molecule. PMID:25300995

Roussel, Guillaume; Michaux, Catherine; Perpète, Eric A

2014-10-01

187

Determination of antihypertensive drug moexipril hydrochloride based on the enhancement effect of sodium dodecyl sulfate at carbon paste electrode.  

PubMed

Herein, an electrochemical differential pulse voltammetric method was developed for the determination of moexipril hydrochloride based on the enhancement effect of sodium dodecyl sulfate. The oxidation process has been carried out in Britton-Robinson buffer. Moexipril hydrochloride exhibits a well-defined irreversible oxidation peak over the entire pH range (2-11). The peak current varied linearly over the range from 4.0 x 10(-7) to 5.2 x 10(-6) mol L(-1). The limits of detection and quantification were 6.87 x 10(-8) mol L(-1) and 2.29 x 10(-7) mol L(-1), respectively. The recovery was found in the range from 99.65% to 100.76%. The relative standard deviation was found in the range from 0.429% to 0.845%. The proposed method possesses high sensitivity, accuracy and rapid response. Finally, this method was successfully used to determine moexipril hydrochloride in tablets. PMID:20188882

Attia, Ali K

2010-04-15

188

Interleukin-6, but not the interleukin-6 receptor plays a role in recovery from dextran sodium sulfate-induced colitis  

PubMed Central

Interleukin (IL)-6-deficient, but not IL-6 receptor (IL-6R)-deficient mice present with a delayed skin wound healing phenotype. Since IL-6 solely signals via the IL-6R and glycoprotein 130 (gp130), Il-6r-deficient mice are expected to exhibit a similar phenotype as Il-6-deficient mice. However, p28 (IL-30) and ciliary neurotrophic factor (CNTF) have been identified as additional low-affinity ligands of the IL-6R/gp130/LIFR complex. IL-6 plays an inflammatory and regenerative role in inflammatory bowel disease (IBD). In the present study, we compared Il-6r-deficient mice with mice treated with neutralizing IL-6 monoclonal antibody (mAb) in a model of dextran sodium sulfate (DSS)-induced colitis. Our results, in agreement with those of previous reports, demonstrated that IL-6 mAbs slightly attenuated DSS-induced colitis during the regeneration phase. Il-6r-deficient mice and mice with tissue-specific deletion of the Il-6r in the myeloid cell lineage (LysMCre) with acute and chronic DSS-induced colitis were, however, indistinguishable from wild-type mice. Our data suggest that IL-6 and IL-6R have an additional role in colitis, apart from the IL-6/IL-6R classic and trans-signaling. PMID:24993179

SOMMER, JAN; ENGELOWSKI, ERIKA; BARAN, PAUL; GARBERS, CHRISTOPH; FLOSS, DOREEN M.; SCHELLER, JURGEN

2014-01-01

189

Caspase-11 is expressed in the colonic mucosa and protects against dextran sodium sulfate-induced colitis.  

PubMed

Ulcerative colitis and Crohn's disease are major inflammatory syndromes that affect millions of patients. Caspase-11 confers protection against Gram-negative enteropathogens, but its role during colitis is unknown. Here, we show that caspase-11 was constitutively expressed in the colon, and that caspase-11-deficient (caspase-11(-/-)) mice were hypersusceptible to dextran sodium sulfate (DSS)-induced colitis. Notably, pro-inflammatory Prevotella species were strongly reduced in the gut microbiota of caspase-11(-/-) mice. Co-housing with wild-type mice leveled Prevotella contents, but failed to protect caspase-11(-/-) mice from increased susceptibility to DSS-induced colitis. We therefore addressed the role of caspase-11 in immune signaling. DSS-induced tissue damage, release of the pyroptosis/necroptosis marker HMGB1, and inflammatory cell infiltration in the gut were markedly increased in caspase-11(-/-) mice. Moreover, caspase-11(-/-) mice showed normal or increased production of mature interleukin (IL)-1? and IL-18, whereas IL-1? and IL-18 secretion was blunted in animals lacking both caspases 1 and 11. In conclusion, we showed that caspase-11 shapes the gut microbiota composition, and that caspase-11(-/-) mice are highly susceptible to DSS-induced colitis. Moreover, DSS-induced inflammasome activation relied on caspase-1, but not caspase-11. These results suggest a role for other caspase-11 effector mechanisms such as pyroptosis in protection against intestinal inflammation. PMID:24850431

Demon, D; Kuchmiy, A; Fossoul, A; Zhu, Q; Kanneganti, T-D; Lamkanfi, M

2014-11-01

190

Inhibition of vasoactive intestinal polypeptide (VIP) induces resistance to dextran sodium sulfate (DSS)-induced colitis in mice.  

PubMed

VIP is highly expressed in the colon and regulates motility, vasodilatation, and sphincter relaxation. However, its role in the development and progress of colitis is still controversial. Our aim was to determine the participation of VIP on dextran sodium sulfate (DSS)-induced colonic mucosal inflammation using VIP(-/-) and WT mice treated with VIP antagonists. Colitis was induced in 32 adult VIP(-/-) and 14 age-matched WT litter-mates by giving 2.5 % DSS in the drinking water. DSS-treated WT mice were injected daily with VIP antagonists, VIPHyb (n?=?22), PG 97-269 (n?=?9), or vehicle (n?=?31). After euthanasia, colons were examined; colonic cytokines mRNA were quantified. VIP(-/-) mice were remarkably resistant to DSS-induced colitis compared to WT. Similarly, DSS-treated WT mice injected with VIPHyb (1 ?M) or PG 97-269 (1 nM) had significantly reduced clinical signs of colitis. Furthermore, colonic expression of IL-1?, TNF-?, and IL-6 was significantly lower in VIP(-/-) and VIPHyb or PG 97-269 compared to vehicle-treated WT. Genetic deletion of VIP or pharmacological inhibition of VIP receptors resulted in resistance to colitis. These data demonstrate a pro-inflammatory role for VIP in murine colitis and suggest that VIP antagonists may be an effective clinical treatment for human inflammatory bowel diseases. PMID:24395090

Vu, John P; Million, Mulugeta; Larauche, Muriel; Luong, Leon; Norris, Joshua; Waschek, James A; Pothoulakis, Charalabos; Pisegna, Joseph R; Germano, Patrizia M

2014-01-01

191

Activation of Intestinal Human Pregnane X Receptor Protects against Azoxymethane/Dextran Sulfate Sodium-Induced Colon Cancer.  

PubMed

The role of intestinal human pregnane X receptor (PXR) in colon cancer was determined through investigation of the chemopreventive role of rifaximin, a specific agonist of intestinal human PXR, toward azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced colon cancer. Rifaximin treatment significantly decreased the number of colon tumors induced by AOM/DSS treatment in PXR-humanized mice, but not wild-type or Pxr-null mice. Additionally, rifaximin treatment markedly increased the survival rate of PXR-humanized mice, but not wild-type or Pxr-null mice. These data indicated a human PXR-dependent therapeutic chemoprevention of rifaximin toward AOM/DSS-induced colon cancer. Nuclear factor ?-light-chain-enhancer of activated B cells-mediated inflammatory signaling was upregulated in AOM/DSS-treated mice, and inhibited by rifaximin in PXR-humanized mice. Cell proliferation and apoptosis were also modulated by rifaximin treatment in the AOM/DSS model. In vitro cell-based assays further revealed that rifaximin regulated cell apoptosis and cell cycle in a human PXR-dependent manner. These results suggested that specific activation of intestinal human PXR exhibited a chemopreventive role toward AOM/DSS-induced colon cancer by mediating anti-inflammation, antiproliferation, and proapoptotic events. PMID:25277138

Cheng, Jie; Fang, Zhong-Ze; Nagaoka, Kenjiro; Okamoto, Minoru; Qu, Aijuan; Tanaka, Naoki; Kimura, Shioko; Gonzalez, Frank J

2014-12-01

192

Role of sol with iron oxyhydroxide/sodium dodecyl sulfate composites on Fenton oxidation of sorbed phenanthrene in sand.  

PubMed

In situ Fenton oxidation has been recently used to oxidize sorbed organic contaminants in soil. The objective of present contribution was to study the role of sodium dodecyl sulfate (SDS) as anionic surfactant and sol with iron oxyhydroxide/SDS for Fenton oxidation of sorbed phenanthrene in sand. The most effective experimental condition for phenanthrene oxidation was the Fenton-like reaction system with 0.35% H2O2, 30 mM SDS, and 4 mM FeCl2. The Fenton-like reactions under these experimental conditions resulted in the production and sustenance of a stable sol with iron oxyhydroxide/SDS composites over 24 h. The formation of iron oxyhydroxide/SDS composites resulted in stabilization of H2O2, and then the Fenton-like reactions were sustained over 24 h. Furthermore, the sol of iron oxyhydroxide/SDS composites gave suitable sites to sustain oxidations of dissolved phenanthrene over a prolonged reaction span, which is required for in situ chemical oxidation. PMID:23666072

Park, Joo-Yang; Kim, Jung-Hwan

2013-09-15

193

Quantification of AAV Particle Titers by Infrared Fluorescence Scanning of Coomassie-Stained Sodium Dodecyl Sulfate-Polyacrylamide Gels  

PubMed Central

Abstract Adeno-associated virus (AAV)-based vectors have gained increasing attention as gene delivery vehicles in basic and preclinical studies as well as in human gene therapy trials. Especially for the latter two—for both safety and therapeutic efficacy reasons—a detailed characterization of all relevant parameters of the vector preparation is essential. Two important parameters that are routinely used to analyze recombinant AAV vectors are (1) the titer of viral particles containing a (recombinant) viral genome and (2) the purity of the vector preparation, most commonly assessed by sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE) followed by silver staining. An important, third parameter, the titer of total viral particles, that is, the combined titer of both genome-containing and empty viral capsids, is rarely determined. Here, we describe a simple and inexpensive method that allows the simultaneous assessment of both vector purity and the determination of the total viral particle titer. This method, which was validated by comparison with established methods to determine viral particle titers, is based on the fact that Coomassie Brilliant Blue, when bound to proteins, fluoresces in the infrared spectrum. Viral samples are separated by SDS–PAGE followed by Coomassie Brilliant Blue staining and gel analysis with an infrared laser-scanning device. In combination with a protein standard, our method allows the rapid and accurate determination of viral particle titers simultaneously with the assessment of vector purity. PMID:22816378

Kohlbrenner, Erik; Henckaerts, Els; Rapti, Kleopatra; Gordon, Ronald E.; Linden, R. Michael; Hajjar, Roger J.

2012-01-01

194

About the singular behavior of the ionic condensation of sodium chondroitin sulfate: Conductivity study in water and water dioxane mixture  

NASA Astrophysics Data System (ADS)

In this work, we generalized the (Bjerrum-Debye-Fuoss-MSA) double layer model to an ellipsoidal polyion (chondroitin sulfate) of (? Zs? e) structural charge, Ls structural length, R minor axe and ( R2 + L2/4) 1/2 major axe. With L ? Ls. Na + counter ions are distributed on the contact (or condensed) layer and on the Debye layer (ionic atmosphere). Both layers are ellipsoidal equipotentials of, respectively, R and d minor axes and are concentric to the polyion. With d = ( R + 1/2 ?), ? is the Debye-MSA screen parameter. The equilibrium distribution of Na + ions is derived from a "two states" statistical approach, leading to a general implicit expression for the rate of condensation (1 - ?). The generality of this formula results from the fact that it takes into account the finite size of the polyion ( L ? ? and R ? 0) and allows to calculate ? for different conformations of the polyion: (ellipsoidal L ? 0, cylindrical: L = Ls, spherical: L ? 0, and Manning's model: RL-1 ? 0). The main conclusion of this model is that, ? obeys to the Ostwald's principle of dilution ( ? ? 1 when CNa+ ? 0). This result is contrary to Manning's theory, for which ? is a constant ?M independent on the concentration Ci: ?M = bS/(? Zi? Lb), with bS = Ls/? Zs? and Lb = e2/( ?kT) is the Bjerrum length. However, our analysis shows that the rate of variation: (? ?/? Ci) in a given range of concentration, depends on the structural parameter bS. Indeed, the critical Manning condition ( ?-1?M = 1, ?(? ?/? Ci) ? 0), is compatible with the general following "rod-like model" approximation: (1-?)?|Zi|(?bS)[4?Zi2Lb][?CiR2];withbS?=?M-1 only for some peculiar values of bS and Lb (i.e., dielectric constant: ?). In water at 25 °C ( ? = 78.3), this singular behavior occurs for a range of a relative low or moderate concentration for some polyelectrolytes of bS structural parameter of about 5.8 Å. This is the case of sodium chondroitin sulfate in water ( bS = 5.72 Å). The addition of dioxane increases Lb, consequently, ? is shifted from its Manning's value. In order to verify this dioxane effect, we have compared experimental equivalent conductibilities ?exp of sodium chondroitin sulfate in water ( no shift) and water-dioxane (60 wt%) mixture ( positive shift), to their theoretical values ?M, ?cthand?sth corresponding, respectively, to the Manning, cylindrical and spherical models. This comparison allows also, to explain the conformation "chosen" by the polyion, in order to minimizing the friction effects (due to: viscosity; ionic and dielectric relaxations) and therefore, to optimize its mobility by the shift of its rate of ionic condensation ?.

M'halla, Jalel; Besbes, Rafik; Bouazzi, Ramzi; Boughammoura, Sondes

2006-01-01

195

Changes in tyrosinase specificity by ionic liquids and sodium dodecyl sulfate.  

PubMed

Tyrosinase is a member of the type 3 copper enzyme family involved in the production of melanin in a wide range of organisms. The ability of tyrosinases to convert monophenols into diphenols has stimulated studies regarding the production of substituted catechols, important intermediates for the synthesis of pharmaceuticals, agrochemicals, polymerization inhibitors, and antioxidants. Despite its enormous potential, the use of tyrosinases for catechol synthesis has been limited due to the low monophenolase/diphenolase activity ratio. In the presence of two water miscible ionic liquids, [BMIM][BF(4)] and ethylammonium nitrate, the selectivity of a tyrosinase from Bacillus megaterium (TyrBm) was altered, and the ratio of monophenolase/diphenolase activity increased by up to 5-fold. Furthermore, the addition of sodium dodecyl sulphate (SDS) at levels of 2-50 mM increased the activity of TyrBm by 2-fold towards the natural substrates L-tyrosine and L-Dopa and 15- to 20-fold towards the non-native phenol and catechol. The R209H tyrosinase variant we previously identified as having a preferential ratio of monophenolase/diphenolase activity was shown to have a 45-fold increase in activity towards phenol in the presence of SDS. We propose that the effect of SDS on the ability of tyrosinase to convert non-natural substrates is due to the interaction of surfactant molecules with residues located at the entrance to the active site, as visualized by the newly determined crystal structure of TyrBm in the presence of SDS. The effect of SDS on R209 may enable less polar substrates such as phenol and catechol, to penetrate more efficiently into the enzyme catalytic pocket. PMID:22539021

Goldfeder, Mor; Egozy, Mor; Shuster Ben-Yosef, Vered; Adir, Noam; Fishman, Ayelet

2013-03-01

196

The Distribution of mixtures of dodecyl ether of poly(23)ethylene glycol with sodium dodecyl sulfate and dodecyltrimethylammonium bromide in the water/octane system  

NASA Astrophysics Data System (ADS)

The scintillation phase and tensiometry methods were used to study the mutual influence of dodecyl ether of poly(23)ethylene glycol (Brij-35) with sodium dodecyl sulfate and Brij-35 with dodecyltrimethylammonium bromide on the distribution in the water/octane system and adsorption at the liquid/liquid interface. The composition of mixed adsorption layers was determined and interaction parameters between molecules were calculated according to the Rosen model.

Soboleva, O. A.; Pronchenko, K. S.; Chernysheva, M. G.; Badun, G. A.

2012-03-01

197

A study of molecular complex formation between propyl gallate and ascorbic acid in the microemulsion phase of sodium dodecyl sulfate, pentanol and water system  

Microsoft Academic Search

The association between two water-soluble antioxidants, i.e. ascorbic acid and propyl gallate have been studied by absorption spectroscopy in microemulsion formed in sodium dodecyl sulfate\\/pentanol\\/water micellar system. It has been shown that propyl gallate forms 1:1 molecular complex with ascorbic acid in every solution. Evolution of the absorption spectra during the study of molecular complex formation goes through well-defined isosbestic

M. Szymula; S. Radzki

2004-01-01

198

Fluorescence probe study of oil-in-water microemulsions. 1. Effect of pentanol and dodecane or toluene on some properties of sodium dodecyl sulfate micelles  

Microsoft Academic Search

The analysis of the decay of the fluorescence of micelle-solubilized pyrene has been used to obtain for the first time the variation of the surfactant aggregation number n in micellar solutions of sodium dodecyl sulfate (SDS) upon addition of increasing amounts of 1-pentanol, and of oil (dodecane or toluene), thereby forming an oil-in-water (o\\/w) microemulsion. The polarity of the microenvironment

Panagiotis Lianos; Jacques Lang; Claude Strazielle; Raoul Zana

1982-01-01

199

Morphological analysis of acute ulcerative colitis experimentally induced by dextran sulfate sodium in the guinea pig: Some possible mechanisms of cecal ulceration  

Microsoft Academic Search

This study in the guinea pig demonstrated that ulcerative colitis-like lesions were induced more rapidly and effectively than\\u000a in other laboratory animals by the oral administration of dextran sulfate sodium (DSS). In all guinea pigs receiving 3% DSS\\u000a solution, diarrhea was noted within 48 h, and bleeding at 48–72 h. Light microscopically, hemorrhagic and ulcerative lesions\\u000a were observed in the

Toshihiko Iwanaga; Osamu Hoshi; Hongxia Han; Tsuneo Fujita

1994-01-01

200

A digitized fluorescence imaging study of intracellular Ca 2+ , pH, and mitochondrial function in primary cultures of rabbit corneal epithelial cells exposed to sodium dodecyl sulfate  

Microsoft Academic Search

Summary  Primary cultures of rabbit corneal epithelial cells have been developed as an in vitro system to predict irritancy potential\\u000a and delayed cytotoxicity of surfactants in our laboratory. The objective of this study was to evaluate the effects of the\\u000a surfactant sodium dodecyl sulfate (SDS), a common ingredient in consumer products, on intracellular Ca2+, pH, and mitochondrial function in this culture

Wei Yang; Daniel Acosta

1995-01-01

201

A Single-Sample Method for Determination of Carbohydrate and Protein Contents Glycoprotein Bands Separated by Sodium Dodecyl Sulfate– Polyacrylamide Gel Electrophoresis  

Microsoft Academic Search

A method is described for determination of carbohydrate and protein contents of glycoproteins separated by sodium dodecyl sulfate–polyacrylamide gel electrophoresis and then electroblotted onto polyvinylidene difluoride (PVDF) membranes. Blots were stained, and appropriate pieces of PVDF membranes were excised, destained, and subjected to sequential hydrolysis with 0.2 M trifluoroacetic acid (TFA) for 1 h at 80°C, then with 2 M

Ewa Zdebska; Jerzy Ko?cielak

1999-01-01

202

Low-temperature synthesis of ZnO nanorods using a seed layer of zinc acetate\\/sodium dodecyle sulfate nanocomposite  

Microsoft Academic Search

Aligned ZnO nanorods were synthesized by a simple hydrothermal method without calcination. A seed layer of zinc acetate (ZnAc2)\\/sodium dodecyle sulfate (SDS) nanocomposite was used for nucleation of ZnO nanorods. First, a ZnAc2\\/SDS composite was deposited on a Si substrate by spin-coating. And then, ZnO nanorods were grown under hydrothermal conditions at 90°C. ZnO crystals were grown in the direction

Naoyuki Ueno; Takanori Maruo; Norikazu Nishiyama; Yasuyuki Egashira; Korekazu Ueyama

2010-01-01

203

A systematic study of bovine serum albumin (BSA) and sodium dodecyl sulfate (SDS) interactions by surface tension and small angle X-ray scattering  

Microsoft Academic Search

Classical parameters obtained from surface tension technique coupled to small angle X-ray scattering (SAXS) measurements gave support to investigate conformational changes in the bovine serum albumin (BSA)–sodium dodecyl sulfate (SDS) complexes, as well as the size of the micelle-like clusters distributed along the polypeptide chain. The studied systems were composed of 1 wt% of BSA in the absence and presence

Sonia F. Santos; Dino Zanette; Hannes Fischer; Rosangela Itri

2003-01-01

204

Studies on sulfite reduction by Desulfovibrio vulgaris.  

PubMed

Dissimilatory reduction of sulfites by Desulfovibrio vulgaris was investigated. Medium with alpha-glycerophosphate as a source of organic carbon and phosphorus was applied. It was found that sulfite at the concentration up to 1M Na2SO3 is not toxic for D. vulgaris and acts efficiently as an electron acceptor. Basing on the presented results, a general mechanism of microbiological transformation of sulfites is proposed. PMID:6174026

Domka, F; Szulczy?ski, M

1981-01-01

205

Sulfite oxidase activity in Thiobacillus novellus.  

PubMed

Thiobacillus novellus shows a maximum induction of sulfite oxidase activity and a maximum growth rate as a result of supplementing the autotrophic growth medium with 4.0 microM ammonium molybdate. Cells grown in the presence of molybdate showed approximately 10-fold increases in the amount of enzyme-associated molybdenum and in the sulfite-to-cytochrome c and sulfite-to-ferricyanide reductase activities. The effect of exogenous molybdate was not discernible with cells grown in the absence of thiosulfate. Tungsten inhibited the growth of T. novellus and the expression of sulfite oxidase activity. PMID:6630156

Southerland, W M; Toghrol, F

1983-11-01

206

Sulfite-Mediated Oxidation of Myeloperoxidase to a Free Radical: Immuno-Spin Trapping Detection in Human Neutrophils  

PubMed Central

Previous studies focused on catalyzed oxidation of (bi)sulfite, leading to the formation of reactive sulfur trioxide (•SO3?), peroxymonosulfate (?O3SOO•) and sulfate (SO4•?) anion radicals, which can damage target proteins and oxidize them to protein radicals. It is known that these very reactive sulfur- and oxygen-centered radicals can be formed by oxidation of (bi)sulfite by peroxidases. Myeloperoxidase (MPO), an abundant heme protein secreted from activated neutrophils that play a central role in host defense mechanisms, allergic reactions and asthma, is a likely candidate for initiating the respiratory damage caused by sulfur dioxide. The objective of the present study is to examine the oxidative damage caused by (bi)sulfite-derived free radicals in human neutrophils through formation of protein radicals. We used immuno-spin trapping and confocal microscopy to study the protein oxidations driven by sulfite-derived radicals. We found that the presence of sulfite can cause MPO-catalyzed oxidation of MPO to a protein radical in phorbol 12-myristate 13-acetate (PMA)-activated human neutrophils. We trapped the MPO-derived radicals in situ using the nitrone spin trap 5,5-dimethyl-1-pyrroline N-oxide (DMPO) and detected them immunologically as nitrone adducts in cells. Our present study demonstrates that myeloperoxidase initiates (bi)sulfite oxidation leading to MPO radical damage possibly leading to (bi)sulfite-exacerbated allergic reactions. PMID:23376232

Ranguelova, Kalina; Rice, Annette B.; Lardinois, Olivier M.; Triquigneaux, Mathilde; Steinckwich, Natacha; Deterding, Leesa J.; Garantziotis, Stavros; Mason, Ronald P.

2013-01-01

207

Existence of a new type of sulfite oxidase which utilizes ferric ions as an electron acceptor in Thiobacillus ferrooxidans.  

PubMed Central

A new type of sulfite oxidase which utilizes ferric ion (Fe3+) as an electron acceptor was found in iron-grown Thiobacillus ferrooxidans. It was localized in the plasma membrane of the bacterium and had a pH optimum at 6.0. Under aerobic conditions, 1 mol of sulfite was oxidized by the enzyme to produce 1 mol of sulfate. Under anaerobic conditions in the presence of Fe3+, sulfite was oxidized by the enzyme as rapidly as it was under aerobic conditions. In the presence of o-phenanthroline or a chelator for Fe2+, the production of Fe2+ was observed during sulfite oxidation by this enzyme under not only anaerobic conditions but also aerobic conditions. No Fe2+ production was observed in the absence of o-phenanthroline, suggesting that the Fe2+ produced was rapidly reoxidized by molecular oxygen. Neither cytochrome c nor ferricyanide, both of which are electron acceptors for other sulfite oxidases, served as an electron acceptor for the sulfite oxidase of T. ferrooxidans. The enzyme was strongly inhibited by chelating agents for Fe3+. The physiological role of sulfite oxidase in sulfur oxidation of T. ferrooxidans is discussed. PMID:3345075

Sugio, T; Katagiri, T; Moriyama, M; Zhen, Y L; Inagaki, K; Tano, T

1988-01-01

208

Sulfite-mediated oxidation of myeloperoxidase to a free radical: immuno-spin trapping detection in human neutrophils.  

PubMed

Previous studies focused on catalyzed oxidation of (bi)sulfite, leading to the formation of the reactive sulfur trioxide ((•)SO3(-)), peroxymonosulfate ((-)O3SOO(•)), and sulfate (SO4(•-)) anion radicals, which can damage target proteins and oxidize them to protein radicals. It is known that these very reactive sulfur- and oxygen-centered radicals can be formed by oxidation of (bi)sulfite by peroxidases. Myeloperoxidase (MPO), an abundant heme protein secreted from activated neutrophils that play a central role in host defense mechanisms, allergic reactions, and asthma, is a likely candidate for initiating the respiratory damage caused by sulfur dioxide. The objective of this study was to examine the oxidative damage caused by (bi)sulfite-derived free radicals in human neutrophils through formation of protein radicals. We used immuno-spin trapping and confocal microscopy to study the protein oxidations driven by sulfite-derived radicals. We found that the presence of sulfite can cause MPO-catalyzed oxidation of MPO to a protein radical in phorbol 12-myristate 13-acetate-activated human neutrophils. We trapped the MPO-derived radicals in situ using the nitrone spin trap 5,5-dimethyl-1-pyrroline N-oxide and detected them immunologically as nitrone adducts in cells. Our present study demonstrates that myeloperoxidase initiates (bi)sulfite oxidation leading to MPO radical damage, possibly leading to (bi)sulfite-exacerbated allergic reactions. PMID:23376232

Ranguelova, Kalina; Rice, Annette B; Lardinois, Olivier M; Triquigneaux, Mathilde; Steinckwich, Natacha; Deterding, Leesa J; Garantziotis, Stavros; Mason, Ronald P

2013-07-01

209

Characterization of Finnish Borrelia burgdorferi sensu lato isolates by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and with monoclonal antibodies.  

PubMed Central

Thirty-seven Borrelia burgdorferi strains, isolated in 1992 from Ixodes ricinus in Finland, were investigated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and by immunoblotting and indirect immunofluorescence assay (IFA) with five to nine monoclonal antibodies (MAbs). By SDS-PAGE results and reactivities to MAbs H3TS, J 8.3, I 17.3, and D6, the 37 isolates were assigned to the species B. burgdorferi sensu stricto (n = 7), Borrelia afzelii (n = 17), or Borrelia garinii (n = 13). Twenty more isolates examined only by IFA and with part of the MAbs were distributed as follows: 9 B. burgdorferi sensu stricto and 11 other species. Among 16 of 37 isolates displaying a SDS-PAGE patterns considered typical of that of B. garinii, 3 were negative by the test with MAb D6; the rest were positive. The three MAb D6-negative isolates reacted with MAb J 8.3 but not with MAb I 17.3. It is suggested that these isolates of a previously undescribed type represent atypical B. afzelii strains deficient in the expression of OspB proteins. The misleading species designation by the SDS-PAGE result is described. The IFA results were generally consistent with those obtained by immunoblotting. The exception was for 3 of 29 isolates that were positive with MAb H5332 by immunoblotting but that were IFA negative. In the present material of 57 strains, all 16 B. burgdorferi sensu stricto isolates originated from the Aland Islands. B. afzelii and B. garinii were isolated from all three regions where ticks were collected. The distributive difference seems to offer a basis for comparative clinico-epidemiological studies of Lyme borreliosis. PMID:7559935

Tuomi, J; Rantamaki, L K; Tanskanen, R; Junttila, J

1995-01-01

210

Suppressive effects of Moringa oleifera Lam pod against mouse colon carcinogenesis induced by azoxymethane and dextran sodium sulfate.  

PubMed

Moringa oleifera Lam (horseradish tree; tender pod or fruits) is a major ingredient in Thai cuisine and has some medicinal properties. Previous studies have shown potentially antioxidant, antitumor promoter, anticlastogen and anticarcinogen activities both in vitro and in vivo. The present study was conducted to investigate chemopreventive effects on azoxymethane (AOM)-initiated and dextran sodium sulfate (DSS)-promoted colon carcinogenesis in mice. Male ICR mice were divided into 8 groups: Group 1 served as a negative control; Group 2 received AOM/DSS as a positive control; Groups 3-5 were fed boiled freeze-dried M. oleifera (bMO) at 1.5%, 3.0% and 6.0%, respectively supplemented in basal diets for 5 weeks; Groups 6-8 were fed with bMO diets at the designed doses above for 2 weeks prior to AOM, during and 1 week after DSS administration. At the end of the study, colon samples were processed for histopathological examination. PCNA indices, and iNOS and COX-2 expression were assessed by immunohistochemistry. The results demonstrated the incidences and multiplicities of tumors in Groups 6-8 to be decreased when compared to Group 2 in a dose dependent manner, but this was significant only in Group 8. The PCNA index was also significantly decreased in Group 8 whereas iNOS and COX-2 protein expression were significantly decreased in Groups 7 and 8. The findings suggest that M. oleifera Lam pod exerts suppressive effects in a colitis-related colon carcinogenesis model induced by AOM/DSS and could serve as a chemopreventive agent. PMID:22471457

Budda, Sirintip; Butryee, Chaniphun; Tuntipopipat, Siriporn; Rungsipipat, Anudep; Wangnaithum, Supradit; Lee, Jeong-Sang; Kupradinun, Piengchai

2011-01-01

211

Iron supplementation increases disease activity and vitamin E ameliorates the effect in rats with dextran sulfate sodium-induced colitis.  

PubMed

Inflammatory bowel disease is often associated with iron deficiency anemia and oral iron supplementation may be required. However, iron may increase oxidative stress through the Fenton reaction and thus exacerbate the disease. This study was designed to determine in rats with dextran sulfate sodium (DSS)-induced colitis whether oral iron supplementation increases intestinal inflammation and oxidative stress and whether the addition of an antioxidant, vitamin E, would reduce this detrimental effect. Four groups of rats that consumed 50 g/L DSS in drinking water were studied for 7 d and were fed: a control, nonpurified diet (iron, 270 mg, and dl-alpha-tocopherol acetate, 49 mg/kg); diet + iron (iron, 3000 mg/kg); diet + vitamin E (dl-alpha-tocopherol acetate, 2000 mg/kg) and the diet + both iron and vitamin E, each at the same concentrations as above. Body weight change, rectal bleeding, histological scores, plasma and colonic lipid peroxides (LPO), plasma 8-isoprostane, colonic glutathione peroxidase (GPx) and plasma vitamin E were measured. Iron supplementation increased disease activity as demonstrated by higher histological scores and heavier rectal bleeding. This was associated with an increase in colonic and plasma LPO and plasma 8-isoprostane as well as a decrease in colonic GPx. Vitamin E supplementation decreased colonic inflammation and rectal bleeding but did not affect oxidative stress, suggesting another mechanism for reducing inflammation. In conclusion, oral iron supplementation resulted in an increase in disease activity in this model of colitis. This detrimental effect on disease activity was reduced by vitamin E. Therefore, the addition of vitamin E to oral iron supplementation may be beneficial. PMID:12368409

Carrier, Julie; Aghdassi, Elaheh; Cullen, Jim; Allard, Johane P

2002-10-01

212

Dextran sulfate sodium-induced colitis-associated neoplasia: a promising model for the development of chemopreventive interventions.  

PubMed

Individuals diagnosed with ulcerative colitis face a significantly increased risk of developing colorectal dysplasia and cancer during their lifetime. To date, little attention has been given to the development of a chemopreventive intervention for this high-risk population. The mouse model of dextran sulfate sodium (DSS) - induced colitis represents an excellent preclinical system in which to both characterize the molecular events required for tumor formation in the presence of inflammation and assess the ability of select agents to inhibit this process. Cyclic administration of DSS in drinking water results in the establishment of chronic colitis and the development of colorectal dysplasias and cancers with pathological features that resemble those of human colitis-associated neoplasia. The incidence and multiplicity of lesions observed varies depending on the mouse strain used (ie, Swiss Webster, C57BL/6J, CBA, ICR) and the dose (0.7%-5.0%) and schedule (1-15 cycles with or without a subsequent recovery period) of DSS. The incidence of neoplasia can be increased and its progression to invasive cancer accelerated significantly by administering DSS in combination with a known colon carcinogen (azoxymethane (AOM), 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), 2-amino-1- methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)) or iron. More recent induction of colitis-associated neoplasia in genetically defined mouse strains has provided new insight into the role of specific genes (ie, adenomatous polyposis coli (Apc), p53, inducible nitric oxide synthase (iNOS), Msh2) in the development of colitis-associated neoplasias. Emerging data from chemopreventive intervention studies document the efficacy of several agents in inhibiting DSS-induced neoplasia and provide great promise that colitis-associated colorectal neoplasia is a preventable disease. PMID:17723178

Clapper, Margie Lee; Cooper, Harry Stanley; Chang, Wen-Chi Lee

2007-09-01

213

Multifunctional activity of a small tellurium redox immunomodulator compound, AS101, on dextran sodium sulfate-induced murine colitis.  

PubMed

Inflammatory bowel diseases (IBDs) are a group of idiopathic, chronic immune-mediated diseases characterized by an aberrant immune response, including imbalances of inflammatory cytokine production and activated innate and adaptive immunity. Selective blockade of leukocyte migration into the gut is a promising strategy for the treatment of IBD. This study explored the effect of the immunomodulating tellurium compound ammonium trichloro (dioxoethylene-o,o') tellurate (AS101) on dextran sodium sulfate (DSS)-induced murine colitis. Both oral and intraperitoneal administration of AS101 significantly reduced clinical manifestations of IBD. Colonic inflammatory cytokine levels (IL-17 and IL-1?) were significantly down-regulated by AS101 treatment, whereas IFN-? was not affected. Neutrophil and ?4?7(+) macrophage migration into the tissue was inhibited by AS101 treatment. Adhesion of mesenteric lymph node cells to mucosal addressin cell adhesion molecule (MAdCAM-1), the ligand for ?4?7 integrin, was blocked by AS101 treatment both in vitro and in vivo. DSS-induced destruction of colonic epithelial barrier/integrity was prevented by AS101, via up-regulation of colonic glial-derived neurotrophic factor, which was found previously to regulate the intestinal epithelial barrier through activation of the PI3K/AKT pathway. Indeed, the up-regulation of glial-derived neurotrophic factor by AS101 was associated with increased levels of colonic pAKT and BCL-2 and decreased levels of BAX. Furthermore, AS101 treatment reduced colonic permeability to Evans blue and decreased colonic TUNEL(+) cells. Our data revealed multifunctional activities of AS101 in the DSS-induced colitis model via anti-inflammatory and anti-apoptotic properties. We suggest that treatment with the small, nontoxic molecule AS101 may be an effective early therapeutic approach for controlling human IBD. PMID:24764299

Halpert, Gilad; Eitan, Tom; Voronov, Elena; Apte, Ron N; Rath-Wolfson, Lea; Albeck, Michael; Kalechman, Yona; Sredni, Benjamin

2014-06-13

214

Effect of sodium lauryl sulfate-induced skin irritation on in vitro percutaneous absorption of four drugs.  

PubMed

The influence of irritant contact dermatitis on percutaneous penetration was investigated for four 14C-labeled compounds with diverse physicochemical properties: hydrocortisone (HC), indomethacin (IM), ibuprofen (IB), and acitretin (AC). Hairless guinea pigs were pretreated in vivo for 24 h with either 0.5% sodium lauryl sulfate (SLS) to induce irritant contact dermatitis or with water (controls). Twenty-four hours after pretreatment animals were sacrificed. Percutaneous penetration was then measured using in vitro diffusion cells and the removed (pretreated) skin. The following parameters were determined: cumulative amount of compound penetrated, steady state flux, lag time, and permeability coefficient, skin concentration per unit area, and the relative amount of drug remaining in the skin (as a percentage of the cumulative amount of compound penetrated through the skin). SLS pretreatment resulted in moderate irritant dermatitis in all animals and increased in vivo transepidermal water loss 4.5 times. Flux was increased in SLS-pretreated skin as compared with controls for all four compounds, with the greatest enhancement for hydrocortisone (HC) (5.9 times), followed by indomethacin (IM) (4.6 times), ibuprofen (IB) (3.9 times), and acitretin (AC) (3.4 times). Skin concentrations increased to a smaller degree from 1.6 times (IB) and 2.6 times (HC) to 3.4 times (IM). However, AC skin concentrations were not different between the two groups. Thus, percutaneous penetration parameters were equivocally influenced by SLS-induced irritation. Increased skin concentrations were paralleled by even higher increases in flux. PMID:1828478

Wilhelm, K P; Surber, C; Maibach, H I

1991-06-01

215

Quantification of sodium lauryl sulfate penetration into the skin and underlying tissue after topical application--pharmacological and toxicological implications.  

PubMed

Sodium lauryl sulfate (SLS) is known to penetrate skin and cause cutaneous irritation. Some of these effects have been well-defined using bioengineering techniques. In this study, the ability of SLS to penetrate skin was quantified in a hairless rat model. In addition, local deep tissue penetration and systemic exposure to SLS were also evaluated to assess the toxic potential of topically applied SLS. SLS was observed to penetrate directly to a depth of about 5-6 mm below the applied site. Systemic redistribution was predominantly responsible in determining concentrations of SLS in tissues deeper than 5-6 mm. Epidermal concentrations of SLS after application of 1% (34 mM) aqueous SLS solution for 24 h were above the threshold levels which are known to evoke typical skin irritation responses. Deeper underlying tissues including dermis, subcutaneous, and muscle may also be exposed to high levels of SLS. Topically applied SLS was also observed in blood and contralateral tissues but the observed levels were not likely to elicit any systemic side effects at these doses. Traces of SLS were observed in tissues 7 days after single 24 h application of SLS, which supports the prolonged barrier disruption data generated using conventional bioengineering techniques. Cumulative treatment of SLS significantly increased the concentration of this compound in the underlying epidermis. The known preferential affinity of SLS for skin lipids and proteins was further confirmed by both in vitro and in vivo results. However, in vitro studies failed to predict the underlying tissue toxicity of SLS under the patch site when compared to the in vivo results. Such quantitative pharmacokinetic-pharmacodynamic correlations may be useful predictors for effective use of surfactants as penetration enhancers in cosmetic, pharmaceutical, and industrial applications. PMID:8801341

Patil, S; Singh, P; Sarasour, K; Maibach, H

1995-10-01

216

Risk analysis of sulfites used as food additives in China.  

PubMed

This study was to analyze the risk of sulfites in food consumed by the Chinese people and assess the health protection capability of maximum-permitted level (MPL) of sulfites in GB 2760-2011. Sulfites as food additives are overused or abused in many food categories. When the MPL in GB 2760-2011 was used as sulfites content in food, the intake of sulfites in most surveyed populations was lower than the acceptable daily intake (ADI). Excess intake of sulfites was found in all the surveyed groups when a high percentile of sulfites in food was in taken. Moreover, children aged 1-6 years are at a high risk to intake excess sulfites. The primary cause for the excess intake of sulfites in Chinese people is the overuse and abuse of sulfites by the food industry. The current MPL of sulfites in GB 2760-2011 protects the health of most populations. PMID:24625409

Zhang, Jian Bo; Zhang, Hong; Wang, Hua Li; Zhang, Ji Yue; Luo, Peng Jie; Zhu, Lei; Wang, Zhu Tian

2014-02-01

217

Compatibility and stability of ondansetron hydrochloride with morphine sulfate and with hydromorphone hydrochloride in 0.9% sodium chloride injection at 4, 22, and 32 degrees C.  

PubMed

The physical compatibility and chemical stability of ondansetron hydrochloride 0.1 and 1 mg/mL with morphine sulfate 1 mg/mL and with hydromorphone hydrochloride 0.5 mg/mL in 0.9% sodium chloride injection were studied. Test solutions of the drugs in 0.9% sodium chloride injection were prepared in triplicate and stored at 4, 22, and 32 degrees C. Samples were removed immediately and at various time points over 31 days and stored at -70 degrees C until analyzed. Physical compatibility was assessed visually and by measuring turbidity with a color-correcting turbidimeter and particle content with a light-obscuration particle sizer and counter. Chemical stability was determined by measuring the concentration of each drug in duplicate with stability-indicating high-performance liquid chromatography. There were no visual or subvisual changes in turbidity or particle content in any of the test solutions at any of the time points. There was little or no loss of any of the drugs. When admixed in 0.9% sodium chloride injection, ondansetron hydrochloride 0.1 and 1 mg/mL plus morphine sulfate 1 mg/mL or hydromorphone hydrochloride 0.5 mg/mL were compatible and stable for at least 7 days at 32 degrees C and for at least 31 days at 4 and 22 degrees C. PMID:7527184

Trissel, L A; Xu, Q; Martinez, J F; Fox, J L

1994-09-01

218

Interactions between hydrophobically modified alkali-swellable emulsion polymers and sodium dodecyl sulfate probed by fluorescence and rheology.  

PubMed

The interactions between a pyrene-labeled hydrophobically modified alkali-swellable emulsion (Py-HASE) polymer and the anionic surfactant sodium dodecyl sulfate (SDS) in aqueous solution were investigated with a fluorometer, a rheometer, and a combination of both instruments to probe the fluorescence of the polymer while the solution was being sheared. Different amounts of SDS were added to two solutions with Py-HASE concentrations of 8 and 57 g/L. The pyrene monomer and excimer decays of the Py-HASE solutions were acquired and globally fitted according to the fluorescence blob model (FBM) and the model free (MF) analysis. Both models yielded the same molar fractions of pyrenes that were isolated, aggregated, or forming excimer by diffusion. The average number of pyrenes per micelle, , was determined according to the FBM and found to equal 2.0 at the SDS concentration corresponding to a maximum in solution viscosity. For a Py-HASE concentration of 57 g/L, the solution viscosities at different SDS concentrations were measured from the Newtonian plateau regions and were found to peak at an SDS concentration of 11 mM. The steady-state fluorescence spectra were acquired at SDS concentrations of 0.1, 6.0, 11.1, and 17 mM while the 57 g/L Py-HASE solution was sheared. Although the solutions of Py-HASE and SDS were found to shear-thin substantially with the solution viscosity decreasing by up to 4 orders of magnitude, no change was observed in the fluorescence spectra acquired at shear rates ranging from 0.005 to 500 s(-1). The overlap of the fluorescence spectra under conditions where the solution viscosity decreased by 4 orders of magnitude suggested that the rearrangement of the hydrophobes from inter- to intramolecular associations that leads to shear-thinning occurs on a time scale that is much faster than that over which the rheology experiments are being conducted. PMID:24364758

Chen, Shaohua; Siu, Howard; Duhamel, Jean

2014-01-01

219

Effects of multi-walled carbon nanotubes on mineralization and mobility of nonylphenol and sodium dodecyl sulfate in agricultural soils  

NASA Astrophysics Data System (ADS)

Nanotechnology is one of the major scientific research fields in this decade. One of the most wide-spread nanomaterials are carbon based nanoparticles (CNPs) which are increasingly be used in industry. Several studies shows that CNPs are interacting with other chemical compounds and organic pollutants in the environment. It is assumed that the interactions between CNPs and organic pollutants are affected by solution and aggregate behavior. Based on the knowledge of the behavior of CNPs and organic pollutants in aquatic systems the interactions of CNPs and organic pollutants in agricultural soils have to be studied. As organic pollutants two environmental substances, nonylphenol (NP) and sodium dodecyl sulfate (SDS) were selected as model substances. They occur frequently in aqueous systems and also show different solubility behavior. As CNP representatives, two different multi-walled carbon nanotubes (MWNT) were selected. They differed either in length or outer diameter. Conclusions therefrom are to be closed the influence of length and diameter of the sorption capacity of different organic pollutants. In addition, two agricultural soils (sandy and silty soil) and one forest soil (sandy soil) were chosen. Mineralization and sorption experiments were conducted to provide information about the degradation of organic pollutants in presence of multi-walled carbon nanotubes in soils. To analyze the CNPs mineralization potential, peroxidase activity was measured. Further extraction experiments were conducted to detect the extractable part of organic pollutants. The results show that the surface area of the MWNT has a significant impact on the sorption behav-ior of NP and SDS in soils. The sorption of NP and SDS is much higher than without MWNT. However, the properties of the organic pollutants (different water solubility and hydrophobicity) are equally important and should be noted. The degradation of both pollutants is influenced by MWNT. Due to the strong sorption of NP and SDS on the MWNT, the degradation of these pollutants in soils, is slower than without MWNT. The peroxidase activity did not contribute to NP and SDS degradation. But the peroxidase activity in agricultural soils is higher than in forest soils. The extractable fraction of NP and SDS is very low and amounts to a maximum of 2 %. Due to the lower degradation of NP and SDS in the presence of MWNT a longer retention of the substances in the soils and potential toxic effects for humans and animals, as a result of plant uptake may be taken into account.

Lillotte, Julia; Marschner, Bernd; Stumpe, Britta

2014-05-01

220

Molecular basis for enzymatic sulfite oxidation: how three conserved active site residues shape enzyme activity.  

PubMed

Sulfite dehydrogenases (SDHs) catalyze the oxidation and detoxification of sulfite to sulfate, a reaction critical to all forms of life. Sulfite-oxidizing enzymes contain three conserved active site amino acids (Arg-55, His-57, and Tyr-236) that are crucial for catalytic competency. Here we have studied the kinetic and structural effects of two novel and one previously reported substitution (R55M, H57A, Y236F) in these residues on SDH catalysis. Both Arg-55 and His-57 were found to have key roles in substrate binding. An R55M substitution increased Km(sulfite)(app) by 2-3 orders of magnitude, whereas His-57 was required for maintaining a high substrate affinity at low pH when the imidazole ring is fully protonated. This effect may be mediated by interactions of His-57 with Arg-55 that stabilize the position of the Arg-55 side chain or, alternatively, may reflect changes in the protonation state of sulfite. Unlike what is seen for SDHWT and SDHY236F, the catalytic turnover rates of SDH R55M and SDHH57A are relatively insensitive to pH (approximately 60 and 200 s(-1), respectively). On the structural level, striking kinetic effects appeared to correlate with disorder (in SDHH57A and SDHY236F) or absence of Arg-55 (SDHR55M), suggesting that Arg-55 and the hydrogen bonding interactions it engages in are crucial for substrate binding and catalysis. The structure of SDHR55M has sulfate bound at the active site, a fact that coincides with a significant increase in the inhibitory effect of sulfate in SDHR55M. Thus, Arg-55 also appears to be involved in enabling discrimination between the substrate and product in SDH. PMID:19004819

Bailey, Susan; Rapson, Trevor; Johnson-Winters, Kayunta; Astashkin, Andrei V; Enemark, John H; Kappler, Ulrike

2009-01-23

221

Merit of quinacrine in the decrease of ingested sulfite-induced toxic action in rat brain.  

PubMed

We aimed at investigating the effects of sulfite-induced lipid peroxidation and apoptosis mediated by secretory phospholipase A2 (sPLA2) on somatosensory evoked potentials (SEP) alterations in rats. Thirty male albino Wistar rats were randomized into three experimental groups as follows; control (C), sodium metabisulfite treated (S), sodium metabisulfite+quinacrine treated (SQ). Sodium metabisulfite (100 mg/kg/day) was given by gastric gavage for 5 weeks and 10 mg/kg/day quinacrine was applied as a single dose of intraperitoneal injection for the same period. The latencies of SEP components were significantly prolonged in the S group and returned to control levels following quinacrine administration. Plasma-S-sulfonate level was increased in S and SQ groups. TBARS levels in the S group were significantly higher than those detected in controls. Quinacrine significantly decreased brain TBARS levels in the SQ group compared with the S group. Quinacrine treatment did not have an effect on the increased sPLA2 level of the sulfite administered group. Immunohistochemistry showed that sulfite caused an increase in caspase-3 and TUNEL positive cells, restored to control levels via quinacrine administration. This study showed that sPLA2 might play a role in ingested sulfite-induced SEP alterations, oxidative stress, apoptotic cell death and DNA damage in the brain. PMID:23168241

Kencebay, Ceren; Derin, Narin; Ozsoy, Ozlem; Kipmen-Korgun, Dijle; Tanriover, Gamze; Ozturk, Nihal; Basaranlar, Goksun; Yargicoglu-Akkiraz, Piraye; Sozen, Berna; Agar, Aysel

2013-02-01

222

Rodent IRR219 (IgGFc?BP) and rTFF3, Expressed Mainly in the Intestinal Mucosa, Depleted During Dextran Sulfate Sodium–Induced Colitis  

Microsoft Academic Search

IgGFc?BP and TFF3 are related with adaptation during injury, mucosal defense, and epithelial healing. In this work, we produced\\u000a the polyclonal antibodies for rat IgGFc?BP or TFF3 and assessed their tissue distributions in adult and prenatal rats, rTFF3\\u000a molecular patterns under reduced and nonreduced condition, involvement of IgGFc?BP, and TFF3 in dextran sulfate sodium (DSS)-induced\\u000a colitis. Polyclonal antibodies of rat

Zao-Ming Feng; Dian-Chun Fang; Wen-Sheng Chen; Rong-Quan Wang

2007-01-01

223

Simulation of blood oxygenation in capillary membrane oxygenators using modified sulfite solution.  

PubMed

Blood oxygenation is the main performance characteristic of capillary membrane oxygenators (CMOs). Handling of natural blood in in vitro investigations of CMOs is quite complex and time-consuming. Since the conventional blood analog fluids (e.g. water/glycerol) lack a substance with an affinity to capture oxygen comparable to hemoglobin's affinity, in this study a novel approach using modified sulfite solution is proposed to address this challenge. The solution comprises sodium sulfite as a component, simulating the role of hemoglobin in blood oxygenation. This approach is validated by OTR (oxygen transfer rate) measured using native porcine blood, in two types of commercially available CMOs. Consequently, the number of complicated natural blood investigations in the evolution procedure of newly developed oxygenators would considerably decrease. Moreover, the reassessing of failed devices, in clinics, would be performed more precisely using a modified sulfite solution than simple water/glycerol testing. PMID:25159916

Tabesh, Hadi; Amoabediny, Ghasem; Rasouli, Ali; Ramedani, Arash; Poorkhalil, Ali; Kashefi, Ali; Mottaghy, Khosrow

2014-12-01

224

Isotope effects associated with the anaerobic oxidation of sulfite and thiosulfate by the photosynthetic bacterium, Chromatium vinosum  

NASA Technical Reports Server (NTRS)

The purple photosynthetic bacterium Chromatium vinosum, strain D, catalyzes several oxidations of reduced sulfur compounds under anaerobic conditions in the light: e.g., sulfide --> sulfur --> sulfate, sulfite --> sulfate, and thiosulfate --> sulfur + sulfate. Here it is shown that no sulfur isotope effect is associated with the last of these processes; isotopic compositions of the sulfur and sulfate produced can differ, however, if the sulfane and sulfonate positions within the thiosulfate have different isotopic compositions. In the second process, an observed change from an inverse to a normal isotope effect during oxidation of sulfite may indicate the operation of 2 enzymatic pathways. In contrast to heterotrophic anaerobic reduction of oxidized sulfur compounds, anaerobic oxidations of inorganic sulfur compounds by photosynthetic bacteria are characterized by relatively small isotope effects.

Fry, B.; Gest, H.; Hayes, J. M.

1985-01-01

225

Effects of buffered vinegar and sodium dodecyl sulfate plus levulinic acid on Salmonella Typhimurium survival, shelf-life, and sensory characteristics of ground beef patties.  

PubMed

The inclusion of two sources of buffered vinegar and sodium dodecyl sulfate plus levulinic acid were studied as interventions for Salmonella Typhimurium and for their effect on shelf-life and sensory characteristics of ground beef. For the Salmonella challenge, beef trimmings (80/20) were inoculated then treated with 2% (w/v) liquid buffered vinegar (LVIN), 2.5% (w/w) powdered buffered vinegar (PVIN), a solution containing 1.0% levulinic acid plus 0.1% sodium dodecyl sulfate (SDLA) at 10% (w/v), or had no intervention applied (CNT). The same trim source and production methods were followed during production of patties for shelf-life and sensory testing without inoculation. SDLA patties had the largest reduction (P<0.05; 0.70 log CFU/g) of Salmonella. However, LVIN and PVIN had the least (P<0.05) psychrotrophic growth. SDLA patties had more purge (P<0.05) and lower (P<0.05) subjective color scores. There were not large differences in sensory characteristics, except PVIN exhibited stronger off-flavor (P<0.05). PMID:23639886

Stelzleni, Alexander M; Ponrajan, Amudhan; Harrison, Mark A

2013-09-01

226

Use of capillary electrophoresis-sodium dodecyl sulfate to monitor disulfide scrambled forms of an Fc fusion protein during purification process.  

PubMed

Overexpression of recombinant Fc fusion proteins in Escherichia coli frequently results in the production of inclusion bodies that are subsequently used to produce fully functional protein by an in vitro refolding process. During the refolding step, misfolded proteins such as disulfide scrambled forms can be formed, and purification steps are used to remove these product-related impurities to produce highly purified therapeutic proteins. A variety of analytical methods are commonly used to monitor protein variants throughout the purification process. Capillary electrophoresis (CE)-based techniques are gaining popularity for such applications. In this work, we used a nonreduced capillary electrophoresis-sodium dodecyl sulfate (nrCE-SDS) method for the analysis of disulfide scrambled forms in a fusion protein. Under denatured nonreduced conditions, an extra post-shoulder peak was observed at all purification steps. Detailed characterization revealed that the peak was related to the disulfide scrambled forms and was isobaric with the correctly folded product. In addition, when sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was used during the CE-SDS peak characterization, we observed that the migration order of scrambled forms is reversed on CE-SDS versus SDS-PAGE. This illustrates the importance of establishing proper correlation of these two techniques when they are used interchangeably to guide the purification process and to characterize proteins. PMID:21420378

Hapuarachchi, Suminda; Fodor, Szilan; Apostol, Izydor; Huang, Gang

2011-07-15

227

Effect of Sodium Lauryl Sulfate-Fumaric Acid Coupled Addition on the In Vitro Rumen Fermentation with Special Regard to Methanogenesis  

PubMed Central

The aim of the current study was to evaluate the effect of sodium lauryl sulfate-fumaric acid coupled addition on in vitro methangenesis and rumen fermentation. Evaluation was carried out using in vitro gas production technique. Ruminal contents were collected from five steers immediately after slaughtering and used for preparation of inoculums of mixed rumen microorganisms. Rumen fluid was then mixed with the basal diet of steers and used to generate four treatments, negative control (no additives), sodium lauryl sulfate (SLS) treated, fumaric acid treated, and SLS-fumaric acid coupled addition treated. The results revealed that, relative to control, efficiency in reduction of methanogenesis was as follows: coupled addition > SLS-addition > fumaric acid addition. Both SLS-addition and SLS-fumaric acid coupled addition demonstrated a decremental effect on ammonia nitrogen (NH3–N), total short chain volatile fatty acids (SCVFAs) concentrations and the amount of substrate degraded, and an increment effect on microbial mass and microbial yield (YATP). Nevertheless, fumaric acid did not alter any of the previously mentioned parameters but induced a decremental effect on NH3–N. Furthermore, both fumaric acid and SLS-fumaric acid coupled addition increased propionate at the expense of acetate and butyrate, while, defaunation increased acetate at the expense of propionate and butyrate. The pH value was decreased by all treatments relative to control, while, cellulase activity did not differ by different treatments. The current study can be promising strategies for suppressing ruminal methane emissions and improving ruminants feed efficiency. PMID:20445794

Abdl-Rahman, M. A.; Sawiress, F. A. R.; Abd El-Aty, A. M.

2010-01-01

228

Intrinsic sulfite content of isolated soy proteins  

Microsoft Academic Search

Commercial isolated soy proteins (ISP) contain 22 and 31 ppm sulfite as measured by the optimized Monier-Williams method (Sulfites\\u000a in Foods, Official Methods of Analysis, 16th edn., AOAC, Washington, DC, 1995, Official Method 990.28). A method was developed to cryogenically trap and quantify\\u000a the sulfur dioxide produced by this method using GC-MS. The same commercial ISP samples were found to

C. J. Stine; W. L. Boatright; G. Lu

2004-01-01

229

Determination of sodium metabisulfite in parenteral formulations by HPIC with suppressed conductivity detection.  

PubMed

Sulfurous compounds: sodium sulfite Na2SO3 (E 221), sodium bisulfite NaHSO, (E 222), and sodium metabisulfite Na2S2O5 (E 223) are largely used as antioxidants in many pharmaceutical formulations. A method for determination of sodium metabisulfite in parenteral formulations containing tartrate ions was developed. High-performance ion chromatography (HPIC) method with suppressed conductivity detection was used. A satisfactory separation of SO(3)2- and SO(4)2- was achieved by the proposed HPIC method with 15 mM NaHCO3/0.6 mM Na2CO3 mobile phase and columns with various packing materials: methacrylate polymer -Allsep A-2 Anion (100 x 4.6 mm, 7 microm) and styrene-divinylbenzene copolymer - IonPac AS14A (250 x 4.0 mm, 7 microm). Use of the Allsep A-2 Anion column provides separation of SO(3)2-, SO(4)2- and C4H4O(4)2- present in the investigated products. The calibration plot was linear for 8-267.3 microg/mL sulfite (r = 0.99978, n = 6) and for 3-165.9 microg/mL sulfate (r = 0.9998, n = 6). The limit of detection for SO(3)(2-) and SO(4)2-were 3 microg/mL and 1 microg/mL, respectively. PMID:21928707

Podolska, Marzena; Bia?ecka, Wanda; Kulik, Anna; Kwiatkowska-Puchniarz, Barbara; Mazurek, Aleksander

2011-01-01

230

Comparison of microenvironments of aqueous sodium dodecyl sulfate micelles in the presence of inorganic and organic salts: a time-resolved fluorescence anisotropy approach.  

PubMed

Microenvironments of aqueous sodium dodecyl sulfate (SDS) micelles was examined in the presence of additives such as sodium chloride and p-toluidine hydrochloride (PTHC) by monitoring the fluorescence anisotropy decays of two hydrophobic probes, 2,5-dimethyl-1,4-dioxo-3,6-diphenylpyrrolo[3,4-c]pyrrole (DMDPP) and coumarin 6 (C6). It has been well-established that SDS micelles undergo a sphere-to-rod transition and that their mean hydrodynamic radius increases from 19 to 100 A upon the addition of 0.0-0.7 M NaCl at 298 K. A similar size and shape transition is induced by PTHC at concentrations that are 20 times lower compared to that of NaCl. This study was undertaken to find out how the microviscosity of the micelles is influenced under these circumstances. It was noticed that the microviscosity of the SDS/NaCl system increased by approximately 45%, whereas there was a less than 10% variation in the microviscosity of the SDS/PTHC system. The large increase in the microviscosity of the former system with salt concentration has been rationalized on the basis of the high concentration of sodium ions in the headgroup region of the micelles and their ability to strongly coordinate with the water present in this region, which decreases the mobility of the probe molecules. PMID:16262297

Dutt, G B

2005-11-01

231

Oxidation inhibition of sulfite in dual alkali flue gas desulfurization system.  

PubMed

A laboratory-scale well-mixed thermostatic reactor with continuously blasting air was used to investigate the oxidation inhibition of sulfite in dual alkali flue gas desulfurization (FGD) system. The effects of operating parameters such as pH value and catalyst concentration on the oxidation were studied. Sodium thiosulfate was used in the system, and was found that it significantly inhabited the sulfite oxidation. In the absence of catalyst, sodium thiosulfate at 12.67 mmol/L had an inhibition efficiency of approximately 98%. While in the presence of catalyst, sodium thiosulfate at 26.72 mmol/L had an inhibition efficiency less than 85.0%. The oxidation reaction order of sulfite in the sodium thiosulfate was determined to be -1.90 and -0.55 in the absence and presence of the catalyst, respectively. Apparent activation energy of oxidation inhibition was calculated to be 53.9 kJ/mol. Pilot tests showed that the consumption rate of thiosulfate agreed well with the laboratory-scale experimental results. PMID:17915734

Mo, Jian-song; Wu, Zhong-biao; Cheng, Chang-jie; Guan, Bao-hong; Zhao, Wei-rong

2007-01-01

232

Evaluation of sodium bicarbonate, chloride, or sulfate with a coccidiostat in corn-soy or corn-soy-meat diets for broiler chickens.  

PubMed

During the period from January to June, combined-sex broiler chickens were inoculated with coccidia via drinking water at 14 d of age. In a completely randomized design (eight replicate pens; 88 chicks per pen) using built-up litter, experimental diets contained monensin plus 0.20% dietary sodium bicarbonate (SBC), which provided 0.054% sodium and 0.144% bicarbonate. Treatment with SBC significantly improved coccidial lesion score, 45-d body weight, and feed efficiency compared with monensin alone. In a 2 x 5 factorial trial using built-up litter pens (eight replicate pens; 88 chicks per pen) vs. each ionophore alone, 0.20% dietary SBC with monensin significantly improved body weight, uniformity, and feed efficiency; 0.20% SBC with halifuginone, lasalocid, monensin, or salinomycin significantly reduced mortality; and 0.20% SBC with lasalocid, monensin, or salinomycin significantly increased breast meat yield. In a 2x4 factorial trial (12 replicate pens; 88 chicks per pen) on built-up litter, corn-soy and corn-soy-meat diets (higher potassium, lower chloride) with monensin were evaluated using 0.054% sodium from SBC, NaCl, or sodium sulfate decahydrate (SSD). With both diet types, SBC (0.20%) or NaCl (0.139% extra) significantly improved weight uniformity, feed efficiency, mortality, and breast meat yield; however, the SSD results were closer to controls. In a 21-d battery brooder test using similar diets and design (2x4 factorial; 4 replicate pens; 10 chicks per pen), SBC and NaCl significantly reduced coccidial lesion scores; SSD produced a significant, but weaker effect. Extra NaCl significantly increased water intake (approximately 37%), water excretion (approximately 27%), and litter moisture (approximately 22%) with both diet types. The SSD did not affect water intake. PMID:10515361

Hooge, D M; Cummings, K R; McNaughton, J L

1999-09-01

233

The Effect of Sodium Dodecyl Sulfate (SDS) and Cetyltrimethylammonium Bromide (CTAB) on the Properties of ZnO Synthesized by Hydrothermal Method  

PubMed Central

ZnO nanostructures were synthesized by hydrothermal method using different molar ratios of cetyltrimethylammonium bromide (CTAB) and Sodium dodecyl sulfate (SDS) as structure directing agents. The effect of surfactants on the morphology of the ZnO crystals was investigated by field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) techniques. The results indicate that the mixture of cationic-anionic surfactants can significantly modify the shape and size of ZnO particles. Various structures such as flakes, sheets, rods, spheres, flowers and triangular-like particles sized from micro to nano were obtained. In order to examine the possible changes in other properties of ZnO, characterizations like powder X-ray diffraction (PXRD), thermogravimetric and differential thermogravimetric analysis (TGA-DTG), FTIR, surface area and porosity and UV-visible spectroscopy analysis were also studied and discussed. PMID:23202952

Ramimoghadam, Donya; Hussein, Mohd Zobir Bin; Taufiq-Yap, Yun Hin

2012-01-01

234

Effect of pH, surface charge and counter-ions on the adsorption of sodium dodecyl sulfate to the sapphire/solution interface  

E-print Network

The role of ionic interactions between sodium dodecyl sulfate, SDS, and sapphire surfaces have been studied using specular neutron reflection to determine the structure and composition of adsorbed surfactant layers. Increasing the pH of the solution from 3 to 9 reduces the adsorption by reversing the charge of the alumina. This occurs at lower pH for the R-plane (1 -1 0 2) than the C-plane (0 0 0 1), corresponding to the different points of zero charge. The largest surface excess is about 6.5 micromol m-2, the thickness of the adsorbed layer is about 24 Angstrom and it contains roughly 20% water. The hydrocarbon tails of the surfactant molecules clearly interpenetrate rather than form an ordered bilayer. The structure is similar in either pure water or in 0.1 M NaCl when the surfactant is at the respective critical micelle concentration. Different structures were seen with lithium and cesium dodecyl sulfate. The CsDS forms dense layers with little or no hydration and a surface excess of about 10.5 micromol m-2. The metal cation strongly influences the hydration of the adsorbed surfactant. An overall picture of 'flattened micelles' for the structure of the adsorbed layer is observed

Ningning Li; Robert K. Thomas; Adrian R. Rennie

2012-05-01

235

ROS, Hsp27, and IKK? Mediate Dextran Sodium Sulfate (DSS) Activation of I?Ba, NF?B, and IL-8  

PubMed Central

Background Dextran sodium sulfate (DSS) is a sulfated polysaccharide that has been very widely used to induce inflammation in experimental models of inflammatory bowel disease in which the effects of pharmacologic and biologic therapies are tested. However, the precise mechanisms by which DSS induces inflammation have not been elucidated. Methods DSS-induced increases in phospho-I?B?, nuclear NF?B (p65), and IL-8 secretion in human colonic epithelial cells in tissue culture are attributable to a reactive oxygen species (ROS)-induced pathway of inflammation, and do not require TLR4, MyD88, or Bcl10, which are associated with the innate immune pathway of NF?B-IL-8 activation. Results DSS-induced increases were inhibited by the ROS scavengers Tempol and Tiron, were associated with decreased phosphorylation of MAPK12 (p38?), MAPK 13 (p38?), and Hsp27, and required the I?B kinase (IKK) signalosome component IKK?. In ex vivo colonic tissue from TLR4-deficient mice, or following knockdown of MyD88 or Bcl10 or exposure to an IRAK 1/4 inhibitor, DSS effects were not suppressed. Data demonstrated that DSS activates I?B?, NF?B, and IL-8 through an ROS-Hsp27-IKK?-mediated pathway, and not through an innate immune cascade. Conclusions These results suggest that DSS models of inflammation may not be optimal for evaluation of interventions that involve mechanisms of innate immunity. PMID:19085995

Bhattacharyya, Sumit; Dudeja, Pradeep K.; Tobacman, Joanne K.

2009-01-01

236

Determining the Oxygen Isotope Equilibrium Fractionation Between Sulfite and Water  

NASA Astrophysics Data System (ADS)

The kinetics of oxygen isotope exchange between water and sulfite have been well studied. However, the scientific community still lacks reliable information for the oxygen isotope equilibrium fractionation between these two species. One reason for the lack of this data is the technical difficulty of extracting sulfite from solution for oxygen isotope analysis. The experimental challenge arises from the fact that sulfite coexists in solution with other S(IV) species, i.e. sulfur dioxide, bisulfite, and pyrosulfite. Extraction techniques such as precipitation of sulfite as barium sulfite or silver sulfite by the addition of barium chloride or silver nitrate induce conversion of non-sulfite species, i.e. sulfur dioxide and pyrosulfite, to sulfite. Each S(IV) species is expected to have a different oxygen isotope equilibrium with water. The wholesale conversion of all S(IV) species to sulfite may induce incorporation of additional oxygen from water and kinetic oxygen isotope effects. Such a conversion would overprint the oxygen isotope signature of sulfite in equilibrium with water and compromise experimental results. We report the first results from our experimental approach to overcome this limitation by using a solid sulfite phase (Ag2SO3, BaSO3, Na2SO3) that is in equilibrium with sulfite in solution. Our goal is to determine both the oxygen isotope equilibrium fractionation between water and sulfite, as well as the isotope equilibrium fractionation between solids and dissolved sulfite. Elucidation of the oxygen isotope equilibrium fractionation between sulfite and water would enable a better understanding of reductive and oxidative sulfur cycling, where sulfite plays a pivotal role as intermediate in both microbial and abiotic processes.

Müller, I.; Brunner, B.; Ferdelman, T. G.

2009-12-01

237

A novel, single-isomer, sulfated cyclodextrin for use as a chiral resolving agent in capillary electrophoresis: the sodium salt of octakis(2,3-di-O-methyl-6-O-sulfo)-?-cyclodextrin  

E-print Network

A novel, single-isomer, sulfated cyclodextrin, the sodium salt of octakis(2,3-di-O-methyl-6-O-sulfo)cyclomaltooctaose (ODMS) was used as a chiral resolving agent in both aqueous and non-aqueous chiral mediated electrophoretic separation of a large...

Busby, Michael Brent

2012-06-07

238

Fermentation to ethanol of pentose-containing spent sulfite liquor  

Microsoft Academic Search

Ethanolic fermentation of spent sulfite liquor with ordinary bakers' yeast is incomplete because of this yeast cannot ferment the pentose sugars in the liquor. This results in poor alcohol yields, and a residual effluent problem. By using the yeast Candida shehatae (R) for fermentation of the spent sulfite liquor from a large Canadian alcohol-producing sulfite pulp and paper mill, pentoses

Shiyuan Yu; Morris Wayman; Sarad K. Parekh

1987-01-01

239

Simultaneous determination of chondroitin sulfate sodium, allantoin and pyridoxine hydrochloride in pharmaceutical eye drops by an ion-pair high-performance liquid chromatography.  

PubMed

An ion-pair high-performance liquid chromatography (HPLC) method has been developed for the simultaneous determination of chondroitin sulfate sodium (CSS), allantoin and pyridoxine hydrochloride (VB(6)) in a commercial eye drops dosage form. An Alltima C(18) column (250 mm x 4.6 mm i.d., 5 microm) was used for the separation at room temperature, with 25 mM ammonium dihydrogen phosphate (containing 0.01% heptanesulfonic acid sodium salt) and acetonitrile (95:5, v/v) as the mobile phase at the flow rate of 0.5 mL min(-1). The detection wavelength for CSS, allantoin and VB(6) was 195 nm, 215 nm and 291 nm, respectively. The method showed good linearity for CSS, allantoin and VB(6), with correlation coefficients greater than 0.9996, in the range of 203.96-815.84 mg L(-1), 371.16-1488.64 mg L(-1), and 23.32-93.28 mg L(-1), respectively. The instrumental and method precisions were adequate with all relative standard deviations lower than 2.0%. The accuracy of this method, measured by the recovery of three compounds from spiked placebo solutions, was from 99.01% to 101.92%. The three components, CSS, allantoin and VB(6) were well separated from other ingredients and degradation products. This method is fast, simple, and can be used for direct and simultaneous determination of CSS, allantoin and VB(6) in the pharmaceutical preparation. PMID:19481898

Jin, Pengfei; Ma, Jie; Wu, Xuejun; Zou, Ding; Sun, Chunhua; Hu, Xin

2009-10-15

240

Structures of complexes of octahaem cytochrome c nitrite reductase from Thioalkalivibrio nitratireducens with sulfite and cyanide.  

PubMed

The structures of complexes of octahaem cytochrome c nitrite reductase from the bacterium Thioalkalivibrio nitratireducens (TvNiR) with the substrate sulfite (1.4 Å resolution; R(cryst) = 0.126) and the inhibitor cyanide (1.55 Å resolution; R(cryst) = 0.148) have been established. The complex with sulfite was prepared by the reduction of the protein crystal with sodium dithionite. The sulfite ion is bound to the iron ion of the catalytic haem through the S atom. The Fe-S distance is 2.24 Å. The structure of the cyanide complex with full occupancy of the ligand site was established for the first time for cytochrome c nitrite reductases. The cyanide ion is bound to the catalytic haem iron through the C atom. The Fe-C distance is 1.91 Å and the Fe-C-N angle is 171°. The sulfite reductase activity of TvNiR was measured at different pH values. The activity is 0.02?µmol of HS(-) per minute per milligram at pH 7.0; it decreases with increasing pH and is absent at pH 9.0. PMID:20944237

Trofimov, Anton A; Polyakov, Konstantin M; Boyko, Konstantin M; Tikhonova, Tamara V; Safonova, Tatyana N; Tikhonov, Alexey V; Popov, Alexandre N; Popov, Vladimir O

2010-10-01

241

Bowman-Birk Inhibitor Concentrate Reduces Colon Inflammation in Mice with Dextran Sulfate Sodium-Induced Ulcerative Colitis  

Microsoft Academic Search

Bowman-Birk inhibitor concentrate (BBIC) is asoybean extract enriched in the BowmanBirk inhibitor, aprotein protease inhibitor. The Bowman-Birk inhibitorcan inhibit proteases released from inflammation mediating cells and suppress superoxide anionradical secretion from immunocytes. This studyinvestigates the ability of Bowman-Birk inhibitorconcentrate to inhibit colon inflammation in the dextransulfate sodium model of ulcerative colitis, aninflammatory bowel disease. When compared to mice on astandard

Jeffrey H. Ware; X. Steven Wan; Paul Newberne; Ann R. Kennedy

1999-01-01

242

Quantification of Desulfovibrio vulgaris dissimilatory sulfite reductase gene expression during electron donor- and electron acceptor-limited growth.  

PubMed

Previous studies have suggested that levels of transcripts for dsrA, a gene encoding a subunit of the dissimilatory sulfite reductase, are not directly related to the rates of sulfate reduction in sediments under all conditions. This phenomenon was further investigated with chemostat-grown Desulfovibrio vulgaris. Under sulfate-limiting conditions, dsrA transcript levels increased as the bulk rates of sulfate reduction in the chemostat increased, but transcript levels were similar at all sulfate reduction rates under electron donor-limiting conditions. When both electron donor- and electron acceptor-limiting conditions were considered, there was a direct correspondence between dsrA transcript levels and the rates of sulfate reduction per cell. These results suggest that dsrA transcript levels may provide important information on the metabolic state of sulfate reducers. PMID:18658285

Villanueva, Laura; Haveman, Shelley A; Summers, Zara M; Lovley, Derek R

2008-09-01

243

Oxidation of ammonium sulfite in aqueous solutions using ozone technology  

NASA Astrophysics Data System (ADS)

How to deal with unstable ammonium sulfite, the byproduct of flue gas desulfuration by ammonia absorption methods, has been a difficult problem in recent years. Oxidation of ammonium sulfite in aqueous solutions using ozone produced by a surface discharge system was investigated in the paper. The oxidation efficiency of ammonium sulfite by ozone and traditional air aeration were compared, and the factors including ozone concentration, gas flow rate, initial concentration of ammonium sulfite solution and reaction temperature were discussed. The results show that the oxidation efficiency of ammonium sulfite by ozone technology reached nearly 100% under the optimum conditions, which had a significant increase compared with that by air aeration.

Li, Yue; Shang, Kefeng; Lu, Na; Li, Jie; Wu, Yan

2013-03-01

244

Oxygen isotope biogeochemistry of pore water sulfate in the deep biosphere: Dominance of isotope exchange reactions with ambient water during microbial sulfate reduction (ODP Site 1130)  

Microsoft Academic Search

Microbially mediated sulfate reduction affects the isotopic composition of dissolved and solid sulfur species in marine sediments. Experiments and field data show that the ?18OSO42- composition is also modified in the presence of sulfate-reducing microorganisms. This has been attributed either to a kinetic isotope effect during the reduction of sulfate to sulfite, cell-internal exchange reactions between enzymatically-activated sulfate (APS), and\\/or

Ulrich G. Wortmann; Boris Chernyavsky; Stefano M. Bernasconi; Benjamin Brunner; Michael E. Böttcher; Peter K. Swart

2007-01-01

245

12 Maple Syrup Digest SULFITE CONCENTRATION  

E-print Network

food color and prolong shelf-life, for the prevention of micro-organism growth, and for maintenance; Health Canada - Food Labelling, 2010). Maple syrup is a natural product free of artificial coloring & Timothy D. Perkinsb INTRODUCTION Sulfites are regulated food additives used as preservatives to maintain

Hayden, Nancy J.

246

VOLATILE COMPONENT RECOVERY FROM SULFITE EVAPORATOR CONDENSATE  

EPA Science Inventory

This study is on the operation and modification of a demonstration unit to remove sulfur dioxide, methanol, furfural, and acetic acid from its sulfite evaporator condensate. This unit consisted of a steam stripper, vent tank SO2 recovery, activated carbon adsorption columns, and ...

247

Intramuscular Cobinamide Sulfite in a Rabbit Model of Sub-Lethal Cyanide Toxicity  

PubMed Central

Objective To determine the ability of an intramuscular cobinamide sulfite injection to rapidly reverse the physiologic effects of cyanide toxicity. Background Exposure to cyanide in fires and industrial exposures and intentional cyanide poisoning by terrorists leading to mass casualties is an ongoing threat. Current treatments for cyanide poisoning must be administered intravenously, and no rapid treatment methods are available for mass casualty cyanide exposures. Cobinamide is a cobalamin (vitamin B12) analog with an extraordinarily high affinity for cyanide that is more water-soluble than cobalamin. We investigated the use of intramuscular cobinamide sulfite to reverse cyanide toxicity induced physiologic changes in a sublethal cyanide exposure animal model. Methods New Zealand white rabbits were given 10 mg sodium cyanide intravenously over 60 minutes. Quantitative diffuse optical spectroscopy and continuous wave near infrared spectroscopy monitoring of tissue oxy- and deoxyhemoglobin concentrations were performed concurrently with blood cyanide level measurements and cobinamide levels. Immediately after completion of the cyanide infusion, the rabbits were injected intramuscularly with cobinamide sulfite (n=6) or inactive vehicle (controls, n=5). Results Intramuscular administration led to rapid mobilization of cobinamide and was extremely effective at reversing the physiologic effects of cyanide on oxyhemoglobin and deoxyhemoglobin extraction. Recovery time to 63% of their baseline values in the central nervous system was in a mean of 1032 minutes in the control group and 9 minutes in the cobinamide group with a difference of 1023 minutes (95% confidence interval [CI] 116, 1874 minutes). In muscle tissue, recovery times were 76 and 24 minutes with a difference of 52 minutes (95% CI 7, 98min). Red blood cell cyanide levels returned towards normal significantly faster in cobinamide sulfite-treated animals than in control animals. Conclusions Intramuscular cobinamide sulfite rapidly and effectively reverses the physiologic effects of cyanide poisoning, suggesting that a compact cyanide antidote kit can be developed for mass casualty cyanide exposures. PMID:20045579

Brenner, Matthew; Kim, Jae G.; Mahon, Sari B.; Lee, Jangwoen; Kreuter, Kelly A.; Blackledge, William; Mukai, David; Patterson, Steve; Mohammad, Othman; Sharma, Vijay S.; Boss, Gerry R.

2009-01-01

248

Identification of Bacillus subtilis CysL, a Regulator of the cysJI Operon, Which Encodes Sulfite Reductase  

Microsoft Academic Search

The way in which the genes involved in cysteine biosynthesis are regulated is poorly characterized in Bacillus subtilis. We showed that CysL (formerly YwfK), a LysR-type transcriptional regulator, activates the transcrip- tion of the cysJI operon, which encodes sulfite reductase. We demonstrated that a cysL mutant and a cysJI mutant have similar phenotypes. Both are unable to grow using sulfate

Isabelle Guillouard; Sandrine Auger; Marie-Francoise Hullo; Farid Chetouani; Antoine Danchin; Isabelle Martin-Verstraete

2002-01-01

249

Effects of sodium tetradecyl sulfate endoscopic variceal sclerotherapy on the esophagus. A prospective clinical and histopathologic study.  

PubMed

A prospective clinical, endoscopic, and histopathologic study of the esophagus was carried out in 24 patients with advanced liver disease who underwent esophageal variceal sclerotherapy (EVS) and who eventually came to autopsy. Patients were arbitrarily divided into three groups: acute (group I), intermediate (group II), and chronic (group III) based on the interval between the first EVS and death. EVS with sodium tetradecyl sulphate (STS) initially produced thrombosis with varying degrees of necrosis and inflammation followed by ulceration, recanalization, and eventually fibrosis with obliteration of varices. Recurrent variceal hemorrhage (VH) leading to death was highest in the acute group since all patients died of uncontrollable VH (100%); it ranged between 50-60% in both the intermediate and chronic groups. Despite variceal obliteration, recurrent hemorrhage developed in the chronic group due to gastric varices or other venous channels in the esophagus or stomach. Additionally, we describe findings not previously reported, such as the presence of sclerosant outside the varices after intravariceal injection, thrombosis of gastric varices after esophageal injections, and the development of muscular wall thickening. PMID:3443730

Kage, M; Korula, J; Harada, A; Mucientes, F; Kanel, G; Peters, R L

1987-12-01

250

Protective effects of different marigold (Calendula officinalis L.) and rosemary cream preparations against sodium-lauryl-sulfate-induced irritant contact dermatitis.  

PubMed

In the present study, we evaluated the protective action of cream preparations containing seven different types of marigold and rosemary extracts in vivo in healthy volunteers with experimentally induced irritant contact dermatitis (ICD). Marigold and rosemary extracts in base cream DAC (Deutscher Arzneimittel-Codex = German Pharmaceutical Codex) were tested in a 4-day repetitive irritation test using sodium lauryl sulfate. The effect was evaluated visually and quantified by noninvasive bioengineering methods, namely chromametry and tewametry. When the test products were applied parallel to the induction period of ICD, a statistically significant protective effect of all cream preparations was observed by all methods. This effect, although not statistically significant, was superior to control by undyed marigold und faradiol ester-enriched extracts in chromametry and by dyed and undyed rosemary extracts in tewametry. The sequential treatment (postirritation) once a day for 5 days was without any effect. Thus, a protective effect of some marigold and rosemary extracts against ICD could be shown in the elicitation phase. PMID:15908760

Fuchs, S M; Schliemann-Willers, S; Fischer, T W; Elsner, P

2005-01-01

251

Inhibitory effects of Dendrobium candidum Wall ex Lindl. on azoxymethane- and dextran sulfate sodium-induced colon carcinogenesis in C57BL/6 mice  

PubMed Central

Dendrobium candidum Wall ex Lindl. was purchased for the evaluation of azoxymethane (AOM)- and dextran sulfate sodium (DSS)-induced colon carcinogenesis in C57BL/6 mice. The body weights of the AOM- and DSS-induced colon cancer control groups were lighter than those of the untreated mice. D. candidum increased the body weights of the mice compared with the control group, and reduced the levels of the serum proinflammatory cytokines, IL-6, IL-12, TNF-? and IFN-?, compared with the colon cancer control group. Reverse transcription-polymerase chain reaction and western blot analyses of the apoptotic-related genes, bax, bcl-2, caspase-3 and caspase-9, were performed in the colon tissues. The high-concentration D. candidum group showed a significant increase in the mRNA and protein expression levels of bax, caspase-3 and caspase-9 and decreased expression levels of bcl-2 compared with the control group. These results indicate that D. candidum Wall ex Lindl. exhibits preventive effects against colon carcinogenesis in mice. PMID:24396476

WANG, QIANG; SUN, PENG; LI, GUIJIE; ZHU, KAI; WANG, CUN; ZHAO, XIN

2014-01-01

252

Bifidobacterium longum Alleviates Dextran Sulfate Sodium-Induced Colitis by Suppressing IL-17A Response: Involvement of Intestinal Epithelial Costimulatory Molecules  

PubMed Central

Although some bacterial strains show potential to prevent colitis, their mechanisms are not fully understood. Here, we investigated the anti-colitic mechanisms of Bifidobacterium longum subsp. infantis JCM 1222T, focusing on the relationship between interleukin (IL)-17A secreting CD4+ T cells and intestinal epithelial costimulatory molecules in mice. Oral administration of JCM 1222T to mice alleviated dextran sulfate sodium (DSS)-induced acute colitis. The expression of type 1 helper T (Th1)- and IL-17 producing helper T (Th17)-specific cytokines and transcriptional factors was suppressed by JCM 1222T treatment. Intestinal epithelial cells (IECs) from colitic mice induced IL-17A production from CD4+ T cells in a cell-cell contact-dependent manner, and this was suppressed by oral treatment with JCM 1222T. Using blocking antibodies for costimulatory molecules, we revealed that epithelial costimulatory molecules including CD80 and CD40, which were highly expressed in IECs from colitic mice, were involved in IEC-induced IL-17A response. Treatment of mice and intestinal epithelial cell line Colon-26 cells with JCM 1222T decreased the expression of CD80 and CD40. Collectively, these data indicate that JCM 1222T negatively regulate epithelial costimulatory molecules, and this effect might be attributed, at least in part, to suppression of IL-17A in DSS-induced colitis. PMID:24255712

Miyauchi, Eiji; Ogita, Tasuku; Miyamoto, Junki; Kawamoto, Seiji; Morita, Hidetoshi; Ohno, Hiroshi; Suzuki, Takuya; Tanabe, Soichi

2013-01-01

253

Electron spin resonance and electron spin echo modulation studies of N,N,N',N'-tetramethylbenzidine photoionization in sodium dodecyl sulfate micelles: structural effects of alcohol addition  

SciTech Connect

Electron spin echo modulation (ESEM) and electron spin resonance (ESR) spectra of the photogenerated N,N,N',N'-tetramethylbenzidine cation radical (TMB/sup +/) in frozen micellar solutions of sodium dodecyl sulfate containing 2-propanol, 1-propanol, 1-pentanol, 1-octanol, 2-propanol-d/sub 7/, and 1-octanol-d/sub 17/ in H/sub 2/O and D/sub 2/O have been studied as a function of the alcohol concentration from 0 to 200 mM. Modulation effects due to the TMB/sup +/ interactions with deuteriums in D/sub 2/O and in 2-propanol-d/sub 7/ or 1-octanol-d/sub 17/ give direct evidence that 2-propanol is mainly located at the micellar interface whereas the alkyl chain of 1-octanol is located deeper into the micelle. Alcohol addition leads to an increase of water penetration into the micellar interface in the order 1-propanol < 2-propanol approx.= 1-pentanol < 1-octanol. The initial efficiency of charge separation upon potoionization of TMB as a function of alcohol concentration correlates with the degree of water penetration into the micelle, but the maximum photoionization efficiency seems more related to the degree of water organization at the micellar surface due to specific perturbing effects on the micellar structure dependent on the alcohol structure.

Baglioni, P.; Kevan, L.

1987-04-09

254

Petal-shaped poly(3,4-ethylenedioxythiophene)/sodium dodecyl sulfate-graphene oxide intercalation composites for high-performance electrochemical energy storage  

NASA Astrophysics Data System (ADS)

A facile and one-step electrochemical codeposition method is introduced for incorporating graphene oxide (GO) into poly(3,4-ethylenedioxythiophene) (PEDOT) films in the presence of sodium dodecyl sulfate (SDS). The as-prepared PEDOT/SDS-GO composites are characterized using scanning electron microscope, transmission electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. The results show that PEDOT/SDS-GO composites possessing a unique petal-shaped morphology have been prepared successfully and exhibit an intercalated microstructure. With the purpose of electrochemical energy storage, the properties of electrochemical capacitance for composites have also been investigated with cyclic voltammetry, galvanostatic charge/discharge measurements, and electrochemical impedance spectroscopy tests. The electrochemical test results manifest the PEDOT/SDS-GO composites have superior capacitive behaviors and cyclic stability, and a high areal capacitance of 79.6 mF cm-2 is achieved at 10 mV s-1 cyclic voltammetry scan. Furthermore, the PEDOT/SDS-GO composites exhibit more superior capacitive performance than that of PEDOT/SDS, indicating the incorporation of GO into the composites effectively boosts the capacitive performance of PEDOT-based supercapacitor electrodes. We consider that this research further extends the application of GO and the composites prepared can be developed as the candidate for the fabrication of low-cost, high-performance supercapacitors for energy storage.

Zhou, Haihan; Han, Gaoyi; Fu, Dongying; Chang, Yunzhen; Xiao, Yaoming; Zhai, Hua-Jin

2014-12-01

255

Comparison of primary human fibroblasts and keratinocytes with immortalized cell lines regarding their sensitivity to sodium dodecyl sulfate in a neutral red uptake cytotoxicity assay.  

PubMed

Cell lines present a valuable tool for in vitro assessment of skin damage caused by application of cosmeticals or pharmaceuticals. They form a reproducible test system under controllable test conditions and, in many cases, can be used as alternatives to animal testing in order to assess the compatibility of drugs or cosmetics and human skin. Yet, it can not necessarily be assumed that the behavior of cultured cells, when treated with different substances, is exactly consistent with the behavior of cells being part of a live organism. Becoming immortal, cells exhibit changes in genotype and/or phenotype, possibly resulting in modified reactions to external influences. Therefore, to obtain results close to in vivo studies, it seems apparent to use primary cells for testing that have not yet undergone any modifications. To compare the properties of primary fibroblasts (Normal Human Dermal Fibroblasts, NHDF) and primary keratinocytes (Normal Human Epidermal Keratinocytes, NHEK) with those of immortal cell lines (3T3 (ACC 173) Swiss albino mouse fibroblasts and HaCaT (human, adult, low calcium, high temperature, human adult skin keratinocytes) cells), their sensitivities in cytotoxicity assays have been assessed. While both fibroblast cell cultures showed similar sensitivities towards sodium dodecyl sulfate (SDS), primary keratinocytes died at SDS concentrations about three times lower than the immortal HaCaT cells. PMID:19402346

Olschläger, Veronika; Schrader, Andreas; Hockertz, Stefan

2009-01-01

256

Ion specific effects in trivalent counterion induced surface and solution self-assembly of the anionic surfactant sodium polyethylene glycol monododecyl ether sulfate.  

PubMed

The effect of different trivalent counterions, Al(3+), Cr(3+), Sc(3+), Gd(3+), and La(3+), on the surface adsorption and Al(3+), Cr(3+), and Sc(3+) for solution self-assembly of the anionic surfactant sodium polyethylene glycol monododecyl ether sulfate has been studied by neutron reflectivity and small angle neutron scattering. The strong binding and complexation between the trivalent counterions and the anionic surfactant result in significant micellar growth and the formation of surface multilayer structures at the air-water interface at relatively low counterion concentrations. Broadly similar surface and solution behaviors are observed for the different trivalent counterions. The evolution in the surface and solution structures in detail depends upon the nature of the counterion, its hydrated radius and its strength of binding. Exceptionally the addition of Cr(3+) counterions have a less pronounced effect. This is attributed to a greater reluctance for exchange within the primary hydration shell for Cr(3+) ions, which results in a shielding of the electrostatic interactions and a reduced surfactant-counterion binding. PMID:24738889

Xu, Hui; Penfold, Jeffrey; Thomas, Robert K; Petkov, Jordan T; Tucker, Ian; Webster, John R P; Grillo, I; Terry, A

2014-04-29

257

RADIOAUTOGRAPHIC VISUALIZATION OF SULFUR-35 DISPOSITION IN THE ARTICULAR CARTILAGE AND BONE OF SUCKLING RATS FOLLOWING INJECTION OF LABELED SODIUM SULFATE  

PubMed Central

The localization of sulfur-35 administered intraperitoneally as sodium sulfate to 7-day-old rats was determined by radioautography of sections of humeri and tibia-knee-femur combinations removed 24, 48, 96, 216, and 290 hours after injection of this isotope. Radioautography of sections of bone and cartilage that had been fixed in formalin indicated that the tracer isotope was present throughout the entire epiphysis. Its concentration therein was highest initially at the epiphyseal-diaphyseal junction where the more mature cartilage cells were present. By the 96th hour post injection the sulfur-35 had become more uniformly distributed in the epiphyses and an even distribution of it throughout the epiphyseal cartilage was almost attained by the 216th hour post injection. As centers of secondary ossification arose in the epiphyseal cartilage, the sulfur-35 appeared to diminish in concentration and disappear from these loci. However, radioautographs of cartilage fixed in formalin saturated with barium hydroxide, instead of in formalin only, disclosed the fact that the tracer isotope was still present in these loci. When bone and bone marrow were fixed in formalin the autographs indicated the presence of sulfur-35 primarily in the periosteum. Only a negligible amount appeared to be present in the bone shaft and marrow. However, when these tissues were fixed in formalin saturated with barium hydroxide it was possible to demonstrate the presence of the tracer isotope in both bone and bone marrow. PMID:14832394

Dziewiatkowski, Dominic D.

1951-01-01

258

Application of the Aqueous Porous Pathway Model to Quantify the Effect of Sodium Lauryl Sulfate on Ultrasound-Induced Skin Structural Perturbation  

PubMed Central

This study investigated the effect of sodium lauryl sulfate (SLS) on skin structural perturbation when utilized simultaneously with low-frequency sonophoresis (LFS). Pig full-thickness skin (FTS) and pig split-thickness skin (STS) treated with LFS/SLS and LFS were analyzed in the context of the aqueous porous pathway model to quantify skin perturbation through changes in skin pore radius and porosity-to-tortuosity ratio (?/?). In addition, skin treatment times required to attain specific levels of skin electrical resistivity were analyzed to draw conclusions about the effect of SLS on reproducibility and predictability of skin perturbation. We found that LFS/SLS-treated FTS, LFS/SLS-treated STS, and LFS-treated FTS exhibited similar skin perturbation. However, LFS-treated STS exhibited significantly higher skin perturbation, suggesting greater structural changes to the less robust STS induced by the purely physical enhancement mechanism of LFS. Evaluation of ?/? values revealed that LFS/SLS-treated FTS and STS have similar transport pathways, while LFS-treated FTS and STS have lower ?/? values. In addition, LFS/SLS treatment times were much shorter than LFS treatment times for both FTS and STS. Moreover, the simultaneous use of SLS and LFS not only results in synergistic enhancement, as reflected in the shorter skin treatment times, but also in more predictable and reproducible skin perturbation. PMID:20963845

Polat, Baris E.; Seto, Jennifer E.; Blankschtein, Daniel; Langer, Robert

2011-01-01

259

Sodium lauryl sulfate increases the efficacy of a topical formulation of foscarnet against herpes simplex virus type 1 cutaneous lesions in mice.  

PubMed

The influence of sodium lauryl sulfate (SLS) on the efficacies of topical gel formulations of foscarnet against herpes simplex virus type 1 (HSV-1) cutaneous infection has been evaluated in mice. A single application of the gel formulation containing 3% foscarnet given 24 h postinfection exerted only a modest effect on the development of herpetic skin lesions. Of prime interest, the addition of 5% SLS to this gel formulation markedly reduced the mean lesion score. The improved efficacy of the foscarnet formulation containing SLS could be attributed to an increased penetration of the antiviral agent into the epidermis. In vitro, SLS decreased in a concentration-dependent manner the infectivities of herpesviruses for Vero cells. SLS also inhibited the HSV-1 strain F-induced cytopathic effect. Combinations of foscarnet and SLS resulted in subsynergistic to subantagonistic effects, depending on the concentration used. Foscarnet in phosphate-buffered saline decreased in a dose-dependent manner the viability of cultured human skin fibroblasts. This toxic effect was markedly decreased when foscarnet was incorporated into the polymer matrix. The presence of SLS in the gel formulations did not alter the viabilities of these cells. The use of gel formulations containing foscarnet and SLS could represent an attractive approach to the treatment of herpetic mucocutaneous lesions, especially those caused by acyclovir-resistant strains. PMID:10952566

Piret, J; Désormeaux, A; Cormier, H; Lamontagne, J; Gourde, P; Juhász, J; Bergeron, M G

2000-09-01

260

Transport pathways and enhancement mechanisms within localized and non-localized transport regions in skin treated with low-frequency sonophoresis and sodium lauryl sulfate.  

PubMed

Recent advances in transdermal drug delivery utilizing low-frequency sonophoresis (LFS) and sodium lauryl sulfate (SLS) have revealed that skin permeability enhancement is not homogenous across the skin surface. Instead, highly perturbed skin regions, known as localized transport regions (LTRs), exist. Despite these findings, little research has been conducted to identify intrinsic properties and formation mechanisms of LTRs and the surrounding less-perturbed non-LTRs. By independently analyzing LTR, non-LTR, and total skin samples treated at multiple LFS frequencies, we found that the pore radii (r(pore)) within non-LTRs are frequency-independent, ranging from 18.2 to 18.5 Å, but significantly larger than r(pore) of native skin samples (13.6 Å). Conversely, r(pore) within LTRs increase significantly with decreasing frequency from 161 to 276 Å and to ? (>300 Å) for LFS/SLS-treated skin at 60, 40, and 20 kHz, respectively. Our findings suggest that different mechanisms contribute to skin permeability enhancement within each skin region. We propose that the enhancement mechanism within LTRs is the frequency-dependent process of cavitation-induced microjet collapse at the skin surface, whereas the increased r(pore) values in non-LTRs are likely due to SLS perturbation, with enhanced penetration of SLS into the skin resulting from the frequency-independent process of microstreaming. PMID:20740667

Polat, Baris E; Figueroa, Pedro L; Blankschtein, Daniel; Langer, Robert

2011-02-01

261

A rapid method of species identification of wild chironomids (Diptera: Chironomidae) via electrophoresis of hemoglobin proteins in sodium dodecyl sulfate polyacrylamide gel (SDS-PAGE).  

PubMed

Studying aquatic benthic macroinvertebrates (BMIs) in the field requires accurate taxonomic identification, which can be difficult and time consuming. Conventionally, head capsule morphology has been used to identify wild larvae of Chironomidae. However, due to the number of species and possible damage and/or deformity of their head capsules, another supporting approach for identification is needed. Here, we provide hemoglobin (Hb) protein in hemolymph of chironomids as a new biomarker that may help resolve some of the ambiguities and difficulties encountered during taxonomic identification. Chironomids collected from two locations in Maine and New Jersey, USA were identified to the genus level and in some cases to the species-level using head capsule and body morphologies. The head capsule for a particular individual was then associated with a corresponding Hb protein profile generated from sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Distinct Hb profiles were observed from one group (Thienemannimyia) and four genera (Chironomus, Cricotopus, Dicrotendipes, and Glyptotendipes) of chironomids. Several species were polymorphic, having more than one Hb profile and/or having bands of the same size as those of other species. However, major bands and the combination of bands could distinguish individuals at the genus and sometimes species-level. Overall, this study showed that Hb profiles can be used in combination with head capsule morphology to identify wild chironomids. PMID:24923437

Oh, J T; Epler, J H; Bentivegna, C S

2014-10-01

262

Role of ?-lipoic acid in dextran sulfate sodium-induced ulcerative colitis in mice: studies on inflammation, oxidative stress, DNA damage and fibrosis.  

PubMed

Ulcerative colitis affects many people worldwide. Inflammation and oxidative stress play a vital role in its pathogenesis. Previously, we reported that ulcerative colitis leads to systemic genotoxicity in mice. The present study was aimed at elucidating the role of ?-lipoic acid in ulcerative colitis-associated local and systemic damage in mice. Experimental colitis was induced using 3%w/v dextran sulfate sodium in drinking water for 2 cycles. ?-Lipoic acid was administered in a co-treatment (20, 40, 80 mg/kg bw) and post-treatment (80 mg/kg bw) schedule. Various biochemical parameters, histological evaluation, comet and micronucleus assays, immunohistochemistry and western blot analysis were employed to evaluate the effect of ?-lipoic acid in mice with ulcerative colitis. The protective effect of ?-lipoic acid was mediated through the modulation of nuclear factor kappa B, cyclooxygenase-2, interleukin 17, signal transducer and activator of transcription 3, nuclear erythroid 2-related factor 2, NADPH: quinone oxidoreductase-1, matrix metalloproteinase-9 and connective tissue growth factor. Further, ulcerative colitis led to an increased gut permeability, plasma lipopolysaccharide level, systemic inflammation and genotoxicity in mice, which was reduced with ?-lipoic acid treatment. The present study identifies the underlying mechanisms involved in ?-lipoic acid-mediated protection against ulcerative colitis and the associated systemic damage in mice. PMID:23793040

Trivedi, P P; Jena, G B

2013-09-01

263

Transport Pathways and Enhancement Mechanisms within Localized and Non-Localized Transport Regions in Skin Treated with Low-Frequency Sonophoresis and Sodium Lauryl Sulfate  

PubMed Central

Recent advances in transdermal drug delivery utilizing low-frequency sonophoresis (LFS) and sodium lauryl sulfate (SLS) have revealed that skin permeability enhancement is not homogenous across the skin surface. Instead, highly perturbed skin regions, known as localized transport regions (LTRs), exist. Despite these findings, little research has been conducted to identify intrinsic properties and formation mechanisms of LTRs and the surrounding less-perturbed non-LTRs. By independently analyzing LTR, non-LTR, and total skin samples treated at multiple LFS frequencies, we found that the pore radii (rpore) within non-LTRs are frequency-independent, ranging from 18.2 – 18.5 Å, but significantly larger than rpore of native skin samples (13.6 Å). Conversely, rpore within LTRs increases significantly with decreasing frequency from 161 Å, to 276 Å, and to ? (>300Å) for LFS/SLS-treated skin at 60 kHz, 40 kHz, and 20 kHz, respectively. Our findings suggest that different mechanisms contribute to skin permeability enhancement within each skin region. We propose that the enhancement mechanism within LTRs is the frequency-dependent process of cavitation-induced microjet collapse at the skin surface, while the increased rpore values in non-LTRs are likely due to SLS perturbation, with enhanced penetration of SLS into the skin resulting from the frequency-independent process of microstreaming. PMID:20740667

Polat, Baris E.; Figueroa, Pedro L.; Blankschtein, Daniel; Langer, Robert

2011-01-01

264

Micellar-enhanced ultrafiltration of copper ions using sodium dodecyl sulfate and its mixture with Brij 35, Tween 80 and Triton X-100.  

PubMed

The performance of copper ion removal using sodium dodecyl sulfate (SDS) and its mixtures with Brij 35, Tween 80 (TW80) and Triton X-100 (TX100) by micellar-enhanced ultrafiltration (MEUF) was investigated. The effects of the molar ratio of nonionic surfactant to SDS on the critical micelle concentration (CMC) of SDS/Brij 35, SDS/TW80 and SDS/TX100, the removal efficiency of Cu(2+), the residual concentration of SDS in the permeate solution and the permeate flux were tested. The results showed that the CMCs of the mixed surfactants were sharply less than that of pure SDS. The removal efficiencies of Cu(2+) were up to the maximum values 98.3 and 95.8% when the molar ratios of Brij 35 and TW80 to SDS were 0.3, and it was 93.5% given 0.7 molar ratio of TX100 to SDS. The concentration of SDS in the permeate decreased dramatically with the addition of nonionic surfactant, and the permeate flux decreased slightly as the molar ratio increased. Compared with the performance by single SDS, the mixed SDS/Brij 35, SDS/TW80 and SDS/TX100 at an optimum composition could result in not only higher rejection of Cu(2+) but also much less dosage of surfactant and concentration of SDS in the permeate. PMID:23676382

Zhao, Baowei; Li, Ruirui; Zhong, Jinkui; Zhang, Li

2013-01-01

265

Sodium sulfate-induced corrosion of pure nickel and superalloy Udimet 700 in a high velocity burner rig at 900 C  

NASA Technical Reports Server (NTRS)

Sodium sulfate-induced corrosion of pure nickel and a commercial nickel-base superalloy, Udimet 700 (U-700), were studied at 900 C in a Mach 0.3 burner rig with different Na levels in the combustor. The corrosion rate of Ni was independent of the Na level in the combustor and considerably lower than that measured in laboratory salt spray tests. The lower rates are associated with the deposition of only a small amount of Na2SO4 on the surface of the NiO scale. Corrosion of U-700 was observed to occur in two stages. During the first stage, the corrosion proceeds by reaction of Cr2O3 scale with the Na2SO4 and evaporation of the Na2CrO4 reaction product from the surface of the corroding sample. Cr depletion in the alloy occurs and small sulfide particles are formed in the Cr depletion zone. Extensive sulfidation occurs during the second state of corrosion, and a thick scale forms. The relationship between the corrosion rate of U-700 and the Na level in the combustor gives a good correlation in the range of 0.3 to 1.5 ppm by weight Na. Very low levels of Na in the combustor cause accelerated oxidation of U-700 without producing the typical hot corrosion morphology.

Misra, A. K.

1987-01-01

266

Evidence for recombination between N- and B-tropic murine leukemia viruses: analysis of three virion proteins by sodium dodecyl sulfate-polyacrylamide gel electrophoresis.  

PubMed Central

We have sodium dodecyl sulfate-polyacrylamide gel electrophoresis to analyze the virion proteins of an N- and a B-tropic C-type virus derived from the BALB/c mouse and 21 putative recombinants, designated XLP-N viruses, obtained from seven crosses between these N- and B-tropic viruses. All the XLP-N viruses are N-tropic but posses the XC plaque morphology of their B-tropic virus parent. Three virion proteins, p15, p30, and gp70, of the parental viruses each differ in electrophoretic mobility. Two recombinants were found that possess a p15 that comigrates with p15 of the B virus; 19 possess a p15 that comigrates with N virus p15. Sixteen recombinants possess a gp70 that migrates like the gp70 of the B virus: four have gp70 with an electrophoretic mobility like that of the N virus gp70. All 21 recombinants possess a p30 that comigrates with p30 of their N virus parent. Given the origin and phenotype of XLP-N viruses, these results would seem to provide good evidence that these viruses are recombinants. Images PMID:197267

Schindler, J; Hynes, R; Hopkins, N

1977-01-01

267

Characterization of Growth, Water Relations, and Proline Accumulation in Sodium Sulfate Tolerant Callus of Brassica napus L. cv Westar (Canola) 1  

PubMed Central

Unselected and sodium sulfate tolerant callus cultures of Brassica napus L. cv Westar were grown on media supplemented with mannitol, NaCl, or Na2SO4. In all cases, growth of tolerant callus, measured on a fresh weight or dry weight basis, was greater than that of unselected callus, which was also subject to necrosis on high levels of salt. Tissue water potential became more negative in both unselected and tolerant callus grown in the presence of mannitol or Na2SO4. Water potentials in unselected callus were more negative than those of the tolerant tissues; but over a range of Na2SO4 concentrations both cultures displayed osmotic adjustment, maintaining relatively constant turgor. Proline accumulation in both unselected and tolerant callus was low (15 to 20 micromoles per gram dry weight) in the absence of stress, but increased on media supplemented with mannitol, NaCl, or Na2SO4. Increases in proline concentration were approximately linear in tolerant callus, reaching a maximum of 130 to 175 micromoles per gram dry weight. In unselected callus, concentrations were higher, reaching 390 to 520 micromoles per gram dry weight. Proline accumulation was correlated with inhibition of growth, and there was a negative correlation between proline concentration and culture age for tolerant callus. PMID:16665381

Chandler, Stephen F.; Thorpe, Trevor A.

1987-01-01

268

Ethanol extract of Cordyceps militaris grown on germinated soybeans attenuates dextran-sodium-sulfate- (DSS-) induced colitis by suppressing the expression of matrix metalloproteinases and inflammatory mediators.  

PubMed

The effect of Cordyceps militaris (CM) grown on germinated soybeans (GSC) in the inflammatory bowel disease (IBD) model was studied. To demonstrate the preventive effect of GSC extract in a dextran-sodium-sulfate- (DSS-) induced acute colitis mouse model, GSC was administered 2 days before DSS coadministration. GSC significantly suppressed DSS-induced disease activity index (DAI) as well as histopathological scores, compared to control or CM-treated group. To elucidate the anti-IBD activity of GSC, we checked the level of matrix metalloproteinases (MMPs) and inflammatory mediators. GSC extract decreased the level of MMP-3 and -9 mRNAs and p53 proteins. The level and activity of LPS-induced MMP-9 were reduced in GSC-treated RAW264.7 cells. It also attenuated the level of inducible nitric oxide synthase (iNOS) and tumor necrosis factor- (TNF-) ? mRNAs both in colon tissue and in macrophage cells. These results suggest that GSC can be applied as a protective agent against IBDs. PMID:23841050

Park, Dong Ki; Park, Hye-Jin

2013-01-01

269

Ethanol Extract of Cordyceps militaris Grown on Germinated Soybeans Attenuates Dextran-Sodium-Sulfate- (DSS-) Induced Colitis by Suppressing the Expression of Matrix Metalloproteinases and Inflammatory Mediators  

PubMed Central

The effect of Cordyceps militaris (CM) grown on germinated soybeans (GSC) in the inflammatory bowel disease (IBD) model was studied. To demonstrate the preventive effect of GSC extract in a dextran-sodium-sulfate- (DSS-) induced acute colitis mouse model, GSC was administered 2 days before DSS coadministration. GSC significantly suppressed DSS-induced disease activity index (DAI) as well as histopathological scores, compared to control or CM-treated group. To elucidate the anti-IBD activity of GSC, we checked the level of matrix metalloproteinases (MMPs) and inflammatory mediators. GSC extract decreased the level of MMP-3 and -9 mRNAs and p53 proteins. The level and activity of LPS-induced MMP-9 were reduced in GSC-treated RAW264.7 cells. It also attenuated the level of inducible nitric oxide synthase (iNOS) and tumor necrosis factor- (TNF-) ? mRNAs both in colon tissue and in macrophage cells. These results suggest that GSC can be applied as a protective agent against IBDs. PMID:23841050

Park, Dong Ki; Park, Hye-Jin

2013-01-01

270

Variation and Genomic Localization of Genes Encoding DROSOPHILA MELANOGASTER Male Accessory Gland Proteins Separated by Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis  

PubMed Central

Accessory gland proteins from Drosophila melanogaster males have been separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis into nine major bands. When individual males from 175 strains were examined, considerable polymorphism for nearly one-half of the major protein bands was seen, including null alleles for three bands. Variation was observed not only among long-established laboratory strains but also among stocks recently derived from natural populations. There was little difference in the amount of variation between P and M strains, indicating that P element mutagenesis is not a factor producing the variation. Codominant expression of variants for each of five bands was found in heterozygotes, suggesting structural gene variation and not posttranslational modification variation. Stocks carrying electrophoretic variants of four of the major proteins were used to map the presumed structural genes for these proteins; the loci were found to be dispersed on the second chromosome. Since males homozygous for variant proteins were fertile, the polymorphism seems to have little immediate effect on successful sperm transfer. We propose that a high degree of polymorphism can be tolerated because these proteins play a nutritive rather than enzymatic role in Drosophila reproduction. PMID:3095182

Whalen, Michael; Wilson, Thomas G.

1986-01-01

271

Chemical and physical stability of citral and limonene in sodium dodecyl sulfate-chitosan and gum arabic-stabilized oil-in-water emulsions.  

PubMed

Citral and limonene are the major flavor components of citrus oils. Both of these compounds can undergo chemical degradation leading to loss of flavor and the formation of undesirable off-flavors. Engineering the interface of emulsion droplets with emulsifiers that inhibit chemical reactions could provide a novel technique to stabilize citral and limonene. At present, emulsified flavor oils are usually stabilized by gum arabic (GA), which is a naturally occurring polysaccharide-protein complex. The objective of this study was to examine if citral and limonene were more stable in emulsions stabilized with a sodium dodecyl sulfate (SDS)-chitosan complex than GA. Citral degraded less in GA-stabilized than in SDS-chitosan-stabilized emulsions at pH 3.0. However, SDS-chitosan-stabilized emulsions were more effective at retarding the formation of the citral oxidation product, p-cymene, than GA-stabilized emulsions. Limonene degradation and the formation of limonene oxidation products, limonene oxide and carvone, were lower in the SDS-chitosan- than GA-stabilized emulsions at pH 3.0. The ability of an SDS-chitosan multilayer emulsifier system to inhibit the oxidative deterioration of citral and limonene could be due to the formation of a cationic and thick emulsion droplet interface that could repel prooxidative metals, thus decreasing prooxidant-lipid interactions. PMID:17419641

Djordjevic, Darinka; Cercaci, Luisito; Alamed, Jean; McClements, D Julian; Decker, Eric A

2007-05-01

272

Sulfate Adsorption on Goethite.  

PubMed

Recent spectroscopic work has suggested that only one surface species of sulfate is dominant on hematite. Sulfate is therefore a very suitable anion to test and develop adsorption models for variable charge minerals. We have studied sulfate adsorption on goethite covering a large range of sulfate concentrations, surface coverages, pH values, and electrolyte concentrations. Four different techniques were used to cover the entire range of conditions. For characterization at low sulfate concentrations, below the detection limit of sulfate with ICP-AES, we used proton-sulfate titrations at constant pH. Adsorption isotherms were studied for the intermediate sulfate concentration range. Acid-base titrations in sodium sulfate and electromobility were used for high sulfate concentrations. All the data can be modeled with one adsorbed species if it is assumed that the charge of adsorbed sulfate is spatially distributed in the interface. The charge distribution of sulfate follows directly from modeling the proton-sulfate adsorption stoichiometry since this stoichiometry is independent of the intrinsic affinity constant of sulfate. The charge distribution can be related to the structure of the surface complex by use of the Pauling bond valence concept and is in accordance with the microscopic structure found by spectroscopy. The intrinsic affinity constant follows from the other measurements. Modeling of the proton-ion stoichiometry with the commonly used 2-pK models, where adsorbed ions are treated as point charges, is possible only if at least two surface species for sulfate are used. Copyright 1999 Academic Press. PMID:10502384

Rietra; Hiemstra; van Riemsdijk WH

1999-10-15

273

Characterization of Dextran Sodium Sulfate-Induced Inflammation and Colonic Tumorigenesis in Smad3?/? Mice with Dysregulated TGF?  

PubMed Central

There are few mouse models that adequately mimic large bowel cancer in humans or the gastrointestinal inflammation which frequently precedes it. Dextran sodium sulphate (DSS)-induces colitis in many animal models and has been used in combination with the carcinogen azoxymethane (AOM) to induce cancer in mice. Smad3?/? mice are deficient in the transforming growth factor beta (TGF?) signaling molecule, SMAD3, resulting in dysregulation of the cellular pathway most commonly affected in human colorectal cancer, and develop inflammation-associated colon cancer. Previous studies have shown a requirement for a bacterial trigger for the colitis and colon cancer phenotype in Smad3?/? mice. Studies presented here in Smad3?/? mice detail disease induction with DSS, without the use of AOM, and show a) Smad3?/? mice develop a spectrum of lesions ranging from acute and chronic colitis, crypt herniation, repair, dysplasia, adenomatous polyps, disseminated peritoneal adenomucinosis, adenocarcinoma, mucinous adenocarcinoma (MAC) and squamous metaplasia; b) the colon lesions have variable galactin-3 (Mac2) staining c) increased DSS concentration and duration of exposure leads to increased severity of colonic lesions; d) heterozygosity of SMAD3 does not confer increased susceptibility to DSS-induced disease and e) disease is partially controlled by the presence of T and B cells as Smad3?/?Rag2?/? double knock out (DKO) mice develop a more severe disease phenotype. DSS-induced disease in Smad3?/? mice may be a useful animal model to study not only inflammation-driven MAC but other human diseases such as colitis cystica profunda (CCP) and pseudomyxomatous peritonei (PMP). PMID:24244446

Brabb, Thea; Maggio-Price, Lillian

2013-01-01

274

Differential sensitivity of duckweeds (Lemnaceae) to sulfite: I. Carbon assimilation and frond replication rate as factors influencing sulfite phytotoxicity  

SciTech Connect

The thiol content and hydrogen sulfide emission responses of duckweeds (Lemnaceae) differentially sensitive to sulfite enrichment were studied, at two levels of irradiance. The objectives were to examine the relationship of selected parameters of sulfite metabolism to sulfite sensitivity, and the role of light level on modifying sulfite metabolic responses and duckweed sulfite sensitivity. Under low light, thiol contents were increased 30 to 40% by sulfite in all three duckweeds examined. Hydrogen sulfide was emitted by all three species, and emission rates were up to four times higher in the sulfite tolerant duckweed Lemna valdiviana. Under high light, sulfite increased thiol contents by an average of 40% in L. valdiviana and Spirodela oligorhiza, but only 20% in Lemna gibba. The greater light enhancement of thiol content exhibited by L. valdiviana and S. oligorhiza may be indicative of larger or more numerous sulfur sinks. Hydrogen sulfide emission rates were also enhanced under high light, and L. gibba exhibited a 17% increase relative to its low light rate. In comparison, L. valdiviana and S. oligorhiza exhibited 55% and 60% increases, respectively. The ability to form elevated internal thiols and hydrogen sulfide were found to be important to sulfite tolerance in duckweeds. Enhancement of both processes under high light may contribute to increased tolerance of sulfite in L. gibba and S. oligorhiza. It is hypothesized that thiol production and hydrogen sulfide emission are important sulfite detoxification processes in duckweeds, and enhancement of sulfite detoxification is fundamental to the modification of duckweed sulfite sensitivity by the photoenvironment. 25 refs., 3 tabs.

Takemoto, B.K.; Noble, R.D.

1986-01-01

275

Labile sulfide and sulfite in phytochelatin complexes  

SciTech Connect

Heavy metals such as cadmium induce tomato cell cultures to synthesize the metal binding polypeptides ({gamma}-Glu-Cys){sub 3} and ({gamma}-Glu-Cys){sub 4}-Gly (phytochelatins). Tomato cells selected for growth on normally lethal concentrations of CdCl{sub 2} synthesize higher quantities of these polypeptides. Cd{sup r} cells are not cross-resistant to other heavy metals, and recent work suggests that metal detoxification by these peptides may be Cd-specific. The occurrence of labile sulfur as a component of the metal complex raises questions concerning possible functions of phytochelatins besides that of Cd binding. The presence of acid-labile sulfide ion in phytochelatin complexes has been reported by several groups. We report the additional finding that labile sulfite is also present in these complexes and in higher amounts than sulfide. Sulfide and sulfite are both released from the metal binding complex by acidification or by treatment with EDTA.

Eannetta, N.T.; Steffens, J.C. (Cornell Univ., Ithaca, NY (USA))

1989-04-01

276

Calibration and measurement uncertainties of a continuous-flow cloud condensation nuclei counter (DMT-CCNC): CCN activation of ammonium sulfate and sodium chloride aerosol particles in theory and experiment  

Microsoft Academic Search

Experimental and theoretical uncertainties in the measurement of cloud condensation nuclei (CCN) with a continuous-flow thermal-gradient CCN counter from Droplet Measurement Technologies (DMT-CCNC) have been assessed by model calculations and calibration experiments with ammonium sulfate and sodium chloride aerosol particles in the diameter range of 20-220 nm. Experiments have been performed in the laboratory and during field measurement campaigns, covering

D. Rose; S. S. Gunthe; E. Mikhailov; G. P. Frank; U. Dusek; M. O. Andreae; U. Pöschl

2008-01-01

277

An Intertwined Evolutionary History of Methanogenic Archaea and Sulfate Reduction  

PubMed Central

Hydrogenotrophic methanogenesis and dissimilatory sulfate reduction, two of the oldest energy conserving respiratory systems on Earth, apparently could not have evolved in the same host, as sulfite, an intermediate of sulfate reduction, inhibits methanogenesis. However, certain methanogenic archaea metabolize sulfite employing a deazaflavin cofactor (F420)-dependent sulfite reductase (Fsr) where N- and C-terminal halves (Fsr-N and Fsr-C) are homologs of F420H2 dehydrogenase and dissimilatory sulfite reductase (Dsr), respectively. From genome analysis we found that Fsr was likely assembled from freestanding Fsr-N homologs and Dsr-like proteins (Dsr-LP), both being abundant in methanogens. Dsr-LPs fell into two groups defined by following sequence features: Group I (simplest), carrying a coupled siroheme-[Fe4-S4] cluster and sulfite-binding Arg/Lys residues; Group III (most complex), with group I features, a Dsr-type peripheral [Fe4-S4] cluster and an additional [Fe4-S4] cluster. Group II Dsr-LPs with group I features and a Dsr-type peripheral [Fe4-S4] cluster were proposed as evolutionary intermediates. Group III is the precursor of Fsr-C. The freestanding Fsr-N homologs serve as F420H2 dehydrogenase unit of a putative novel glutamate synthase, previously described membrane-bound electron transport system in methanogens and of assimilatory type sulfite reductases in certain haloarchaea. Among archaea, only methanogens carried Dsr-LPs. They also possessed homologs of sulfate activation and reduction enzymes. This suggested a shared evolutionary history for methanogenesis and sulfate reduction, and Dsr-LPs could have been the source of the oldest (3.47-Gyr ago) biologically produced sulfide deposit. PMID:23028926

Susanti, Dwi; Mukhopadhyay, Biswarup

2012-01-01

278

Applications of pulsed EPR spectroscopy to structural studies of sulfite oxidizing enzymes().  

PubMed

Sulfite oxidizing enzymes (SOEs), including sulfite oxidase (SO) and bacterial sulfite dehydrogenase (SDH), catalyze the oxidation of sulfite (SO(3) (2-)) to sulfate (SO(4) (2-)). The active sites of SO and SDH are nearly identical, each having a 5-coordinate, pseudo-square-pyramidal Mo with an axial oxo ligand and three equatorial sulfur donor atoms. One sulfur is from a conserved Cys residue and two are from a pyranopterindithiolene (molybdopterin, MPT) cofactor. The identity of the remaining equatorial ligand, which is solvent-exposed, varies during the catalytic cycle. Numerous in vitro studies, particularly those involving electron paramagnetic resonance (EPR) spectroscopy of the Mo(V) states of SOEs, have shown that the identity and orientation of this exchangeable equatorial ligand depends on the buffer pH, the presence and concentration of certain anions in the buffer, as well as specific point mutations in the protein. Until very recently, however, EPR has not been a practical technique for directly probing specific structures in which the solvent-exposed, exchangeable ligand is an O, OH(-), H(2)O, SO(3) (2-), or SO(4) (2-) group, because the primary O and S isotopes ((16)O and (32)S) are magnetically silent (I = 0). This review focuses on the recent advances in the use of isotopic labeling, variable-frequency high resolution pulsed EPR spectroscopy, synthetic model compounds, and DFT calculations to elucidate the roles of various anions, point mutations, and steric factors in the formation, stabilization, and transformation of SOE active site structures. PMID:23440026

Klein, Eric L; Astashkin, Andrei V; Raitsimring, Arnold M; Enemark, John H

2013-01-01

279

Longitudinal analysis of inflammation and microbiota dynamics in a model of mild chronic dextran sulfate sodium-induced colitis in mice  

PubMed Central

AIM: To characterize longitudinally the inflammation and the gut microbiota dynamics in a mouse model of dextran sulfate sodium (DSS)-induced colitis. METHODS: In animal models, the most common method used to trigger colitis is based on the oral administration of the sulfated polysaccharides DSS. The murine DSS colitis model has been widely adopted to induce severe acute, chronic or semi-chronic colitis, and has been validated as an important model for the translation of mice data to human inflammatory bowel disease (IBD). However, it is now clear that models characterized by mild intestinal damage are more accurate for studying the effects of therapeutic agents. For this reason, we have developed a murine model of mild colitis to study longitudinally the inflammation and microbiota dynamics during the intestinal repair processes, and to obtain data suitable to support the recovery of gut microbiota-host homeostasis. RESULTS: All plasma cytokines evaluated, except IL-17, began to increase (P < 0.05), after 7 d of DSS administration. IL-17 only began to increase 4 d after DSS withdrawal. IL-1? and IL-17 continue to increase during the recovery phase, even when clinical signs of colitis had disappeared. IL-6, IL-10 and IFN-? reached their maxima 4 d after DSS withdrawal and decreased during the late recovery phase. TNF? reached a peak (a three- fold increase, P < 0.05), after which it slightly decreased, only to increase again close to the end of the recovery phase. DSS administration induced profound and rapid changes in the mice gut microbiota. After 3 d of DSS administration, we observed a major reduction in Bacteroidetes/Prevotella and a corresponding increase in Bacillaceae, with respect to control mice. In particular, Bacteroidetes/Prevotella decreased from a relative abundance of 59.42%-33.05%, while Bacillaceae showed a concomitant increase from 2.77% to 10.52%. Gut microbiota rapidly shifted toward a healthy profile during the recovery phase and returned normal 4 d after DSS withdrawal. Cyclooxygenase 2 expression started to increase 4 d after DSS withdrawal (P < 0.05), when dysbiosis had recovered, and continued to increase during the recovery phase. Taken together, these data indicated that a chronic phase of intestinal inflammation, characterized by the absence of dysbiosis, could be obtained in mice using a single DSS cycle. CONCLUSION: Dysbiosis contributes to the local and systemic inflammation that occurs in the DSS model of colitis; however, chronic bowel inflammation is maintained even after recovery from dysbiosis. PMID:24587679

De Fazio, Luigia; Cavazza, Elena; Spisni, Enzo; Strillacci, Antonio; Centanni, Manuela; Candela, Marco; Pratico, Chiara; Campieri, Massimo; Ricci, Chiara; Valerii, Maria Chiara

2014-01-01

280

Deletion of cationic amino acid transporter 2 exacerbates dextran sulfate sodium colitis and leads to an IL-17-predominant T cell response  

PubMed Central

l-Arginine (l-Arg) is a semiessential amino acid that has altered availability in human ulcerative colitis (UC), a form of inflammatory bowel disease, and is beneficial in murine colitis induced by dextran sulfate sodium (DSS), a model with similarity to UC. We assessed the role of cationic amino acid transporter 2 (CAT2), the inducible transporter of l-Arg, in DSS colitis. Expression of CAT2 was upregulated in tissues from colitic mice and localized predominantly to colonic macrophages. CAT2-deficient (CAT2?/?) mice exposed to DSS exhibited worsening of survival, body weight loss, colon weight, and histological injury. These effects were associated with increased serum l-Arg and decreased tissue l-Arg uptake and inducible nitric oxide synthase protein expression. Clinical benefits of l-Arg supplementation in wild-type mice were lost in CAT2?/? mice. There was increased infiltration of macrophages, dendritic cells, granulocytes, and T cells in colitic CAT2?/? compared with wild-type mice. Cytokine profiling revealed increases in proinflammatory granulocyte colony-stimulating factor, macrophage inflammatory protein-1?, IL-15, and regulated and normal T cell-expressed and -secreted and a shift from an IFN-?- to an IL-17-predominant T cell response, as well as an increase in IL-13, in tissues from colitic CAT2?/? mice. However, there were no increases in other T helper cell type 2 cytokines, nor was there a global increase in macrophage-derived proinflammatory cytokines. The increase in IL-17 derived from both CD4 and ?? T cells and was associated with colonic IL-6 expression. Thus CAT2 plays an important role in controlling inflammation and IL-17 activation in an injury model of colitis, and impaired l-Arg availability may contribute to UC pathogenesis. PMID:23703655

Singh, Kshipra; Coburn, Lori A.; Barry, Daniel P.; Asim, Mohammad; Scull, Brooks P.; Allaman, Margaret M.; Lewis, Nuruddeen D.; Washington, M. Kay; Rosen, Michael J.; Williams, Christopher S.; Chaturvedi, Rupesh

2013-01-01

281

The Noncommensal Bacterium Methylococcus capsulatus (Bath) Ameliorates Dextran Sulfate (Sodium Salt)-Induced Ulcerative Colitis by Influencing Mechanisms Essential for Maintenance of the Colonic Barrier Function  

PubMed Central

Dietary inclusion of a bacterial meal has recently been shown to efficiently abolish soybean meal-induced enteritis in Atlantic salmon. The objective of this study was to investigate whether inclusion of this bacterial meal in the diet could abrogate disease development in a murine model of epithelial injury and colitis and thus possibly have therapeutic potential in human inflammatory bowel disease. C57BL/6N mice were fed ad libitum a control diet or an experimental diet containing 254 g/kg of body weight BioProtein, a bacterial meal consisting of Methylococcus capsulatus (Bath), together with the heterogenic bacteria Ralstonia sp., Brevibacillus agri, and Aneurinibacillus sp. At day 8, colitis was induced by 3.5% dextran sulfate sodium (DSS) ad libitum in the drinking water for 6 days. Symptoms of DSS treatment were less profound after prophylactic treatment with the diet containing the BioProtein. Colitis-associated parameters such as reduced body weight, colon shortening, and epithelial damage also showed significant improvement. Levels of acute-phase reactants, proteins whose plasma concentrations increase in response to inflammation, and neutrophil infiltration were reduced. On the other, increased epithelial cell proliferation and enhanced mucin 2 (Muc2) transcription indicated improved integrity of the colonic epithelial layer. BioProtein mainly consists of Methylococcus capsulatus (Bath) (88%). The results that we obtained when using a bacterial meal consisting of M. capsulatus (Bath) were similar to those obtained when using BioProtein in the DSS model. Our results show that a bacterial meal of the noncommensal bacterium M. capsulatus (Bath) has the potential to attenuate DSS-induced colitis in mice by enhancing colonic barrier function, as judged by increased epithelial proliferation and increased Muc2 transcription. PMID:23064342

Hult, Lene T. Olsen; Spetalen, Signe; Kaldhusdal, Magne; Christofferesen, Trine Eker; Bengtsson, Oskar; Romarheim, Odd Helge; Jacobsen, Morten; Lea, Tor

2013-01-01

282

Ginsenoside Metabolite Compound K Promotes Recovery of Dextran Sulfate Sodium-Induced Colitis and Inhibits Inflammatory Responses by Suppressing NF-?B Activation  

PubMed Central

Phytogenic compounds with anti-oxidant and anti-inflammatory properties, such as ginsenoside metabolite compound K (CK) or berberine (BBR), are currently discussed as promising complementary agents in the prevention and treatment of cancer and inflammation. The latest study showed that ginsenoside Rb1 and its metabolites could inhibit TNBS-induced colitis injury. However, the functional mechanisms of anti-inflammation effects of ginsenoside, particularly its metabolite CK are still not clear. Here, using dextran sulfate sodium (DSS)-induced colitis in mice, clinical parameters, intestinal integrity, pro-inflammatory cytokines production, and signaling pathways in colonic tissues were determined. In mild and sever colitis mice, CK and BBR (as a positive agent) alleviated colitis histopathology injury, ameliorated myeloperoxidase (MPO) activity, reduced pro-inflammatory cytokines production, such as, IL-6, IL-1?, TNF-?, and increased anti-inflammatory cytokine IL-10 production in both mice colon tissues and blood. Nevertheless, the results revealed that CK and BBR inhibited NF-?B p65 nuclear translocation, downregulated p-I?B? and upregulated I?B?, indicating that CK, as well as BBR, suppressed the activation of the NF-?B pathway in the progression of colitis with immunofluorescence, immunohistochemical and western blotting analysis. Furthermore, CK inhibited pro-inflammatory cytokines production in LPS-activated macrophages via down-regulation of NF-?B signaling pathway. Taken together, our results not only reveal that CK promotes the recovery of the progression of colitis and inhibits the inflammatory responses by suppressing NF-?B activation, but also suggest that CK downregulates intestinal inflammation through regulating the activation of macrophages and pro-inflammatory cytokines production. PMID:24504372

Li, Juan; Zhong, Wei; Wang, Weiwei; Hu, Shaoping; Yuan, Jiahui; Zhang, Bing; Hu, Tianhui; Song, Gang

2014-01-01

283

The noncommensal bacterium Methylococcus capsulatus (Bath) ameliorates dextran sulfate (Sodium Salt)-Induced Ulcerative Colitis by influencing mechanisms essential for maintenance of the colonic barrier function.  

PubMed

Dietary inclusion of a bacterial meal has recently been shown to efficiently abolish soybean meal-induced enteritis in Atlantic salmon. The objective of this study was to investigate whether inclusion of this bacterial meal in the diet could abrogate disease development in a murine model of epithelial injury and colitis and thus possibly have therapeutic potential in human inflammatory bowel disease. C57BL/6N mice were fed ad libitum a control diet or an experimental diet containing 254 g/kg of body weight BioProtein, a bacterial meal consisting of Methylococcus capsulatus (Bath), together with the heterogenic bacteria Ralstonia sp., Brevibacillus agri, and Aneurinibacillus sp. At day 8, colitis was induced by 3.5% dextran sulfate sodium (DSS) ad libitum in the drinking water for 6 days. Symptoms of DSS treatment were less profound after prophylactic treatment with the diet containing the BioProtein. Colitis-associated parameters such as reduced body weight, colon shortening, and epithelial damage also showed significant improvement. Levels of acute-phase reactants, proteins whose plasma concentrations increase in response to inflammation, and neutrophil infiltration were reduced. On the other, increased epithelial cell proliferation and enhanced mucin 2 (Muc2) transcription indicated improved integrity of the colonic epithelial layer. BioProtein mainly consists of Methylococcus capsulatus (Bath) (88%). The results that we obtained when using a bacterial meal consisting of M. capsulatus (Bath) were similar to those obtained when using BioProtein in the DSS model. Our results show that a bacterial meal of the noncommensal bacterium M. capsulatus (Bath) has the potential to attenuate DSS-induced colitis in mice by enhancing colonic barrier function, as judged by increased epithelial proliferation and increased Muc2 transcription. PMID:23064342

Kleiveland, Charlotte R; Hult, Lene T Olsen; Spetalen, Signe; Kaldhusdal, Magne; Christofferesen, Trine Eker; Bengtsson, Oskar; Romarheim, Odd Helge; Jacobsen, Morten; Lea, Tor

2013-01-01

284

Serum amino acids profile and the beneficial effects of L-arginine or L-glutamine supplementation in dextran sulfate sodium colitis.  

PubMed

This study was conducted to investigate serum amino acids profile in dextran sulfate sodium (DSS)-induced colitis, and impacts of graded dose of arginine or glutamine supplementation on the colitis. Using DSS-induced colitis model, which is similar to human ulcerative colitis, we determined serum profile of amino acids at day 3, 7, 10 and 12 (5 days post DSS treatment). Meanwhile, effects of graded dose of arginine (0.4%, 0.8%, and 1.5%) or glutamine (0.5%, 1.0% and 2.0%) supplementation on clinical parameters, serum amino acids, colonic tight junction proteins, colonic anti-oxidative indicators [catalase, total superoxide dismutase (T-SOD), glutathione peroxidase (GSH-Px)], colonic pro-inflammatory cytokines [interleukin-1 beta (IL-1?), IL-6, IL-17 and tumor necrosis factor alpha (TNF-?)] in DSS-induced colitis were fully analyzed at day 7 and 12. Additionally, the activation of signal transduction pathways, including nuclear factor kappa B (NF-?B), mitogen-activated protein kinases (MAPK), phosphoinositide-3-kinases (PI3K)/PI3K-protein kinase B (Akt), and myosin light chain kinase (MLCK)-myosin light chain (MLC20), were analyzed using immunoblotting. Serum amino acids analysis showed that DSS treatment changed the serum contents of amino acids, such as Trp, Glu, and Gln (P<0.05). Dietary arginine or glutamine supplementation had significant (P<0.05) influence on the clinical and biochemical parameters (T-SOD, IL-17 and TNF-?) in colitis model. These results were associated with colonic NF-?B, PI3K-Akt and MLCK signaling pathways. In conclusion, arginine or glutamine could be a potential therapy for intestinal inflammatory diseases. PMID:24505477

Ren, Wenkai; Yin, Jie; Wu, Miaomiao; Liu, Gang; Yang, Guan; Xion, Yan; Su, Dingding; Wu, Li; Li, Tiejun; Chen, Shuai; Duan, Jielin; Yin, Yulong; Wu, Guoyao

2014-01-01

285

Fluorescence probe study of oil-in-water microemulsions. 1. Effect of pentanol and dodecane or toluene on some properties of sodium dodecyl sulfate micelles  

SciTech Connect

The analysis of the decay of the fluorescence of micelle-solubilized pyrene has been used to obtain for the first time the variation of the surfactant aggregation number n in micellar solutions of sodium dodecyl sulfate (SDS) upon addition of increasing amounts of 1-pentanol, and of oil (dodecane or toluene), thereby forming an oil-in-water (o/w) microemulsion. The polarity of the microenvironment of the micelle-solubilized pyrene, the intramicellar rate constant k/sub E/ for pyrene excimer formation, and the microviscosity eta sensed by dipyrenylpropane (DPyP) upon intramolecular excimer formation have been also investigated. The results indicate that the addition of pentanol to concentrated (> 0.2 M) SDS solutions results in an increase of n and a decrease of k/sub E/, eta, and microenvironment polarity. These effects have been associated with the transformation of the initially spherical SDS micelles into anisotropic (disk-shaped) large micelles upon dissolution of pentanol in the micelles. Upon addition of dodecane, eta goes through a minimum in the case of concentrated SDS + pentanol systems, but only shows a monotonous increase for less concentrated SDS + pentanol systems. For the former the variation of n has been attributed to a change of micelle shape from nonspherical to spherical, whereas for the latter the initially spherical micelles remain spherical upon dodecane solubilization. Similar variations of n are observed when dodecane is replaced by toluene in the case of dilute SDS + pentanol systems, whereas large differences are noted for concentrated SDS + pentanol systems. In the case where the results suggest the formation of oil-in-water microemulsion droplets, the calculations indicate that the oil core permeates part of the surfactant alkyl chains.

Lianos, P.; Lang, J.; Strazielle, C.; Zana, R.

1982-03-18

286

Effects of Dietary Glutamine on the Homeostasis of CD4+ T Cells in Mice with Dextran Sulfate Sodium-Induced Acute Colitis  

PubMed Central

This study investigated the effects of dietary glutamine (Gln) on T-helper (Th) and T regulatory (Treg) cell homeostasis and colonic inflammatory mediator expression in mice with dextran sulfate sodium (DSS)-induced colitis. Mice were randomly assigned to 4 groups with 2 normal control (C and G) and 2 DSS-treated groups (DC and DG). The C and DC groups were fed a common semipurified diet, while the G and DG groups received an identical diet except that part of the casein was replaced by Gln, which provided 25% of the total amino acid nitrogen. Mice were fed the diets for 10 days. On day 6, mice in the normal control groups were given distilled water, while those in the DSS groups were given distilled water containing 1.5% DSS for 5 d. At the end of the experiment, the mice were sacrificed for further examination. Results showed that DC group had higher plasma haptoglobin, colonic weight, immunoglobulin G, inflammatory cytokine and nuclear factor (NF)-?B protein levels. Gln administration lowered inflammatory mediators and NF-?B/I?B? ratio in colitis. Compared with the DC group, the percentages of interleukin-17F and interferon-? in blood and transcription factors, T-bet and RAR-related orphan receptor-?t, gene expressions in mesenteric lymph nodes were lower, whereas blood Foxp3 was higher in the DG group. Also, DG group had lower colon injury score. These results suggest that Gln administration suppressed Th1/Th17 and Th-associated cytokine expressions and upregulated the expression of Tregs, which may modulate the balance of Th/Treg and reduce inflammatory reactions in DSS-induced colitis. PMID:24416230

Hsiung, Yuan-Chin; Liu, Jun-Jen; Hou, Yu-Chen; Yeh, Chiu-Li; Yeh, Sung-Ling

2014-01-01

287

Dextran sodium sulfate-induced inflammation alters the expression of proteins by intestinal Escherichia coli strains in a gnotobiotic mouse model.  

PubMed

To identify Escherichia coli proteins involved in adaptation to intestinal inflammation, mice were monoassociated with the colitogenic E. coli strain UNC or with the probiotic E. coli strain Nissle. Intestinal inflammation was induced by treating the mice with 3.5% dextran sodium sulfate (DSS). Differentially expressed proteins in E. coli strains collected from cecal contents were identified by 2-dimensional difference gel electrophoresis. In both strains, acute inflammation led to the downregulation of pathways involved in carbohydrate breakdown and energy generation. Accordingly, DSS-treated mice had lower concentrations of bacterial fermentation products in their cecal contents than control mice. Differentially expressed proteins also included the Fe-S cluster repair protein NfuA, the tryptophanase TnaA, and the uncharacterized protein YggE. NfuA expression was 3-fold higher in E. coli strains from DSS-treated than from control mice. Reporter experiments confirmed the induction of nfuA in response to iron deprivation, mimicking Fe-S cluster destruction by inflammation. YggE expression, which has been reported to reduce the intracellular level of reactive oxygen species, was 4- to 8-fold higher in E. coli Nissle than in E. coli UNC. This was confirmed by in vitro reporter gene assays indicating that Nissle is better equipped to cope with oxidative stress than UNC. Nissle isolated from DSS-treated and control mice had TnaA levels 4- to 7-fold-higher than those of UNC. Levels of indole resulting from the TnaA reaction were higher in control animals associated with E. coli Nissle. Because of its anti-inflammatory effect, indole is hypothesized to be involved in the extension of the remission phase in ulcerative colitis described for E. coli Nissle. PMID:22210207

Schumann, Sara; Alpert, Carl; Engst, Wolfram; Loh, Gunnar; Blaut, Michael

2012-03-01

288

Hepatic early inflammation induces downregulation of hepatic cytochrome P450 expression and metabolic activity in the dextran sulfate sodium-induced murine colitis.  

PubMed

Ulcerative colitis (UC) patients may have increased concentrations of drugs in their blood. We hypothesized that this response is mainly due to a decrease in the expression and activity of the drug-metabolizing enzyme, cytochrome P450 (CYP), in the liver. In this study, we have tried to demonstrate the hypothesis. UC was induced in mice by treatment with dextran sulfate sodium (DSS) solution. The mRNA and protein expression levels of CYP, inflammatory cytokine levels, and the metabolic activity of CYP3A in the liver were measured. The nuclear translocations of nuclear factor kappa B (NF-?B), pregnane X receptor (PXR), and constitutive androstane receptor (CAR) were analyzed. The levels of hepatic inflammatory cytokines increased in the DSS-treated group. The hepatic mRNA and protein expression of CYP (CYP1A, CYP2C, CYP2D, CYP2E, and CYP3A) and the CYP3A metabolic activity significantly decreased compared to the control group. Hepatic NF-?B nuclear translocation significantly increased in the DSS-treated group. In contrast, the nuclear translocations of PXR and CAR were decreased. Lipopolysaccharides from inflammatory sites in the colon induce hepatic inflammation in DSS-induced murine colitis. This inflammation then causes an increase in the nuclear translocation of hepatic NF-?B and a decrease in the nuclear translocation of PXR and CAR, resulting in the decreased expression and activities of CYP. The results of this study indicated that at the onset of UC, the decreased activity of hepatic CYP causes an increase in the concentrations of drugs in the blood, leading to an increase in the incidence of adverse reactions. PMID:24413062

Kusunoki, Yoshiki; Ikarashi, Nobutomo; Hayakawa, Yoshitaka; Ishii, Makoto; Kon, Risako; Ochiai, Wataru; Machida, Yoshiaki; Sugiyama, Kiyoshi

2014-04-11

289

Spontaneous formation of nanocubic particles and spherical vesicles in catanionic mixtures of ester-containing gemini surfactants and sodium dodecyl sulfate in the presence of electrolyte.  

PubMed

Self-assembly of pure ester-containing cationic gemini surfactants, dodecyl esterquat, and dodecyl betainate geminis, and cation-rich catanionic mixtures of them with sodium dodecyl sulfate (SDS) were investigated using surface tension, electrical conductivity, dynamic light scattering (DLS), transmission electron microscopy (TEM) and cyclic voltammetry (CV) measurements in the absence and presence of KCl. Different physicochemical properties such as the critical micelle concentration (CMC), degree of counterion dissociation (?diss), interfacial properties, morphology of aggregates, and interparticle interaction parameters were determined. Both geminis formed micelles in the absence of KCl, and mixing with SDS did not change the morphology; just a growth in micelle size was observed. However, the aggregation behavior of these geminis with respect to the position of the ester bond in the alkyl chain appeared completely different in the presence of KCl. Esterquat gemini formed cubic nanoparticles (or cobosomes) in the presence of [KCl] = 0.05 M and transformed into spherical micelles upon increasing the surfactant concentration. By contrast, betainate gemini formed vesicles in the presence of [KCl] = 0.05 M and subsequently converted to micelles as the surfactant concentration increased. The morphology of esterquat gemini (in the presence of 0.05 M KCl) after mixing with SDS changed from cubic nanoparticles (or cobosomes) to cylindrical nanoparticles coexistent with cobosomes. Betainate gemini remained vesicular upon mixing with SDS, and no dramatic structural change of aggregates took place. The morphology changes of aggregates upon mixing with SDS were explained from calculating the interactions between two gemini surfactants and SDS on the basis of regular solution theory. PMID:24547744

Aghdastinat, Hasti; Javadian, Soheila; Tehrani-Bagha, Alireza; Gharibi, Hussein

2014-03-20

290

Conformation of a Protein Kinase C Substrate, NG(28-43), and Its Analog in Aqueous and Sodium Dodecyl Sulfate Micell Solutions  

PubMed Central

A peptide corresponding to the neuronal protein neurogranin (NG) residues 28-43, NG(28-43), and its analog, [A35]NG(28-43), have been investigated by NMR, electron paramagnetic resonance (EPR), and circular dichroism (CD) spectroscopies. The peptides existed in aqueous solution predominantly in radom form. However, a nascent helical structure was detected in the central region of the parent peptide from NMR data. Furthermore, a helical structure can be detected for both peptides with greater induced secondary structure for the parent peptide in the presence of sodium dodecyl sulfate (SDS) micelle. The formation of micelles for SDS was confirmed by results from EPR as well as 13C NMR. As shown by CD experiments, helical conformer was induced for NG(28-43) in vesicular solution containing phosphatidyl serine (PS), whereas no helix can be discerned for the peptide in phosphatidyl choline (PC)-containing vesicular solution. Together with the induction of the peptide into helix in SDS micellar solution as suggested by both NMR and CD data, these results underscored the electrostatic contribution to the interaction of the PKC substrate peptides and proteins with membrane. According to NMR and CD data, a dynamic equilibrium existed between free and micelle-bound states for the peptide. Moreover, proton-deuterium exchange results and SDS-induced linewidth broadening of proton resonances allowed delineation of the orientation of the amphipathic helix on the surface of SDS micelle. The result was supported by spin label experiments that indicated F35 of NG(28-43) interacted strongly with the hydrocarbon interior of micelle. Based on the experimental findings, a working model was proposed that attempted to partly explain the roles played by the nonpolar amino acid near the phosphorylation site, by the negatively charged phospholipids, and by the basic amino acids of the substrate. ImagesFIGURE 15 PMID:9017186

Chang, Ding-Kwo; Chien, Wei-Jyun; Arunkumar, A. I.

1997-01-01

291

Location of spectroscopic probes in self-aggregating assemblies. II. The location of pyrene and other probes in sodium dodecyl sulfate micelles.  

PubMed

The location of pyrene in sodium dodecyl sulfate (SDS) micelles is determined as a function of the aggregation number, N, by exploiting the fact that spin probes 5- and 16-doxyl stearic acid methyl esters (5DSE and 16DSE, respectively) are effective quenchers of pyrene fluorescence. The locations of the two spin probes are known from Part 1 of this series (J. Phys. Chem. B 2006, 110, 9791) and the distance between the probes and pyrene is determined by using a hydrodynamic theory to predict the quenching rate constant. The hydrodynamic theory requires the microviscosity of the regions through which the probe and pyrene diffuse. The same spin probe that serves as quencher provides a measure of the microviscosity; thus, all the information needed to locate pyrene is available from each spin probe. Employing 5DSE, at N = 53, pyrene is found to diffuse through a zone 67% of which lies within the Stern layer and 33% in the core. As the micelle grows, due to increasing either the surfactant or added-salt concentration, this diffusion zone moves outward such that, at N = 130, near the sphere-rod transition, it lies approximately 75% within the Stern layer and 25% in the core. Employing 16DSE, the location of pyrene is within 0.4 A of that found from 5DSE at low values of N and within 0.8 A at high values. Full information required to locate pyrene by using the currently developed method is not yet available for other spin probes and other commonly employed quenchers; nevertheless, using a variety of strategies and reasonable assumptions leads to the same location of pyrene within the uncertainties of the method. All of the spectroscopic probes employed in this study are largely located within the polar shell of the micelles, the largest departure being about 4% of the diameter of the micelle. PMID:17488113

Lebedeva, Nataly; Ranganathan, Radha; Bales, Barney L

2007-05-31

292

Chemical and physical properties of high-yield alkaline sulfite green liquor  

SciTech Connect

The majority of sodium sulfite pulping liquor recovery systems are based on the reductive burning of the spent liquor, followed by acidification of the resulting smelt solution by CO[sub 2]. This study investigated a number of the physical and chemical properties of the resulting green liquor which might be relevant to the optimum design of this type of sulfite and carbonate recovery system for an alkaline sulfite high-yield process. CO[sub 2] gas does generate H[sub 2]S when bubbled through green liquor; however, a large amount of solid soon is formed. Continuing the flow leads to increased amounts of H[sub 2]S, but the ratio of H[sub 2]S to CO[sub 2] remains less than 1.0. Solutions more highly concentrated in Na[sub 2]S absorb relatively more CO[sub 2], regardless of the ratios of H[sub 2]S to CO[sub 2] in the initial gas stream. The percentage of H[sub 2]S released increases with increasing Na[sub 2]S concentration. Stripping the green liquor with inert gas, steam, or vacuum does not improve the H[sub 2]S removal efficiency. The maximum CO[sub 2] pressure can be generated by decomposing pure 6 M NaHCO[sub 3]. If the starting material is a bicarbonate/carbonate mixture, conversion is incomplete and a portion of the NaHCO[sub 3] forms a dead load.

Sell, N.J.; Norman, J.C. (Univ. of Wisconsin, Green Bay, WI (United States). Natural and Applied Sciences)

1993-11-01

293

Dose-dependent effect of nutritional sulfite intake on visual evoked potentials and lipid peroxidation.  

PubMed

The aim of this study was to clarify the dose-dependent effect of sulfite (SO?²?) ingestion on brain and retina by means of electrophysiological and biochemical parameters. Fifty two male Wistar rats, aged 3 months, were randomized into four experimental groups of 13 rats as follows; control (C), sulfite treated groups (S(1); 10 mg/kg/day, S?; 100mg/kg/day, S?; 260 mg/kg/day). Control rats were administered distilled water, while the other three groups were given sodium metabisulfite (Na?S?O?) of amounts mentioned above, via gavage for a period of 35 days. All components of visual evoked potential (VEP) were prolonged in S? and S? groups compared with S? and C groups. Plasma-S-sulfonate levels, which are an indicator of sulfur dioxide (SO?) exposure, were increased in Na?S?O? treated groups in a dose-dependent manner. Furthermore, the significant increments in thiobarbituric acid reactive substances (TBARS) and 4-hydroxy-2-nonenal (4-HNE) levels occurred with increasing intake of Na?S?O?. Though not significant, glutathione (GSH) and oxidized glutathione (GSSG) levels were observed to decrease with increasing doses of Na?S?O?. In conclusion, Na?S?O? treatment in rats caused a dose-dependent increase in lipid peroxidation and all VEP latencies. The data indicate that lipid peroxidation could play an important role in sulfite toxicity. PMID:20875852

Ozturk, Nihal; Yargicoglu, Piraye; Derin, Narin; Akpinar, Deniz; Agar, Aysel; Aslan, Mutay

2011-01-01

294

Sodium metabisulfite--a marker for cosmetic allergy?  

PubMed

A 45-year-old woman developed dermatitis of the face after she applied a cosmetic package comprising day and night creams. Patch tests were performed with the British Contact Dermatitis Society (BCDS) standard, bases + preservatives, and cosmetic series in addition to samples of both creams and the individual constituents. She had positive tests to both cosmetic creams, sodium sulfite from the manufacturer's samples (5% white soft paraffin (WSP)), and sodium metabisulfite (1% pet) in our bases + preservatives battery. Sodium sulfite is a constituent of both cosmetic creams. We assume that the positive test to sodium metabisulfite is a cross-reaction. We hypothesize that a reaction to sodium metabisulfite may be a marker for sulfite allergy in cosmetics and might account for some of the unexplained positives in previous reports. PMID:17343630

Malik, Mohsin M; Hegarty, Mary A; Bourke, John F

2007-04-01

295

Hippocampal neuron number loss in rats exposed to ingested sulfite.  

PubMed

Sulfite, which is continuously formed in the body during metabolism of sulfur-containing amino acids, is commonly used in preservatives. It has been shown that there are toxic effects of sulfite on many cellular components. The aim of this study was to investigate the possible toxic effects of sulfite on pyramidal neurons by counting cell numbers in CA1 and CA2-CA3 subdivisions of the rat hippocampus. For this purpose, male albino rats were divided into a control group and a sulfite group (25 mg/kg). Sulfite was administered to the animals via drinking water for 8 weeks. At the end of the experimental period, brains were removed and neurons were estimated in total and in a known fraction of CA1 and CA2-CA3 subdivisions of the left hippocampus by using the optical fractionator method--a stereological method. Results showed that sulfite treatment caused a significant decrease in the total number of pyramidal neurons in three subdivisions of the hippocampus (CA1 and CA2-CA3) in the sulfite group compared with the control group (p < 0.05, Mann Whitney U test). It was concluded that exogenous administration of sulfite causes loss of pyramidal neurons in CA1 and CA2-CA3 subdivisions of the rat hippocampus. PMID:21511899

Akdogan, Ilgaz; Kocamaz, Erdogan; Kucukatay, Vural; Yonguc, Nilufer Goksin; Ozdemir, Mehmet Bulent; Murk, William

2011-10-01

296

Oxidation rate of magnesium sulfite catalyzed by cobalt ions.  

PubMed

Oxidation of magnesium sulfite is important for recycle of byproduct in the magnesium desulfurization. The oxidation rate of magnesium sulfite, prepared by vacuum evaporation method, was investigated in a bubbling tank in presence of transition metal catalysts, which shows cobalt is the most effective. The general reaction orders with respect to cobalt, magnesium sulfite, and oxygen are 0.44, 0, and 0.46, respectively, and the apparent activity energy is 17.43 KJ·mol. The catalytic performance of cobalt compared with other metals was also analyzed employing the ion potential theory. Integrated with the three-phase reaction model, we inferred that the general oxidation rate of magnesium sulfite is controlled by mass transfer of oxygen. Further, the intrinsic kinetics was predicted, indicating that the reaction orders with respect to cobalt and oxygen are 1.0 and 0, respectively. The results are helpful for the recycle of magnesium sulfite in magnesia desulfurization. PMID:24588305

Qiangwei, Li; Lidong, Wang; Yi, Zhao; Yongliang, Ma; Shuai, Cui; Shuang, Liu; Peiyao, Xu; Jiming, Hao

2014-04-01

297

Synthesis and evaluation of sodium deoxycholate sulfate as a lipid drug carrier to enhance the solubility, stability and safety of an amphotericin B inhalation formulation.  

PubMed

Amphotericin B (AmB) is still used as the gold standard for therapy against invasive fungal diseases. However, the use of AmB through oral administration is restricted due to its low solubility and stability in aqueous solution, which is the cause for its poor bioavailability and highly varying absorption. Therefore, an attempt has been made to enhance the solubility and stability of AmB to evaluate its bioactivity and safety for use as an inhaler by using a new excipient sodium deoxycholate sulfate (SDS) with aim of using it as a drug carrier for AmB. Therefore, SDS was formulated together with AmB as a dry powder by lyophilization. The dry powder was reconstituted in distilled water and evaluated its physicochemical properties such as zeta potential, particle size and pH to compare its solubility and stability of the formulations with a SDC-AmB (i.e., known as Fungizone(®)). In vitro toxicity studies were carried out with red blood cells (RBC) and respiratory cell lines. Bioactivity was determined by a micro-dilution method against Candidaalbicans and Cryptococcusneoformans. We found that SDS-AmB had a zeta potential (-45.53 mV), which was higher than of Fungizone(®); and produced a stable particle size in solution (73.8 nm). The particle size distributions of both formulations were expressed as their mass median aerodynamic diameters (MMAD; 1.70 and 1.74 ?m), their fine particle fractions (FPF; 70 and 80%) and geometric standard deviations (GSD; 2.3 and 2.0), respectively. These values indicated that the sizes were appropriate for use in an inhaler. Pure AmB was found to hemolyse RBC and was very toxic to alveolar macrophage cells, as their viability rapidly declined from 93 to 56% when the AmB concentration increased from 1 to 8 ?g/mL. The SDS-AmB formulation had a significantly reduced toxicity compared to AmB. The results clearly indicated that the SDS-lipid based nanoparticles had the potential to be used as an alternative option to Fungizone(®) for an AmB formulation for inhalation. PMID:24907597

Gangadhar, Katkam N; Adhikari, Kajiram; Srichana, Teerapol

2014-08-25

298

Structure, interfacial properties, and dynamics of the sodium alkyl sulfate type surfactant monolayer at the water/trichloroethylene interface: a molecular dynamics simulation study.  

PubMed

In this work, we perform a series of molecular dynamics (MD) simulations on the category of sodium alkyl sulfate (SDS-type) surfactant monolayers at the water/trichloroethylene (TCE) interface. Three separate tail-length SDS-type molecules are used. We investigate the conformation of surfactant chain (i.e., packing, orientation, and order), interfacial properties (i.e., interfacial thickness, interfacial tension, area compressibility, and bending modulus), their dependence on the chain length, and the average area per surfactant chain. We also examine the behavior of the surfactant monolayer in the metastable regime of negative surface tension with reference to collapse. The simulation has clearly shown that the very dilute monolayer is well described as a two-dimensional gas. With the increase of interfacial surfactant coverage, the monolayer is in the liquid-expanded (LE) phase. The surfactant tails at the interface become straighter, more ordered, and thicker at higher surfactant coverage. At the same time, interfacial tension of long-tail systems is always lower than that of short-tail systems. In the LE phase, the area compressibility modulus and the bending modulus increase with an increase in tail length. With a further decrease in molecular areas, the monolayer with large negative surface tension becomes unstable. Our simulations show that buckling of the monolayers is of dynamic nature as a response to mechanical instability. The further transformation pathway from buckling to bud can be controlled by the bending modulus, which depends crucially on the tail length and interfacial surfactant coverage. At a given area per molecule, the short tail chain makes the monolayer softer, and the budding process becomes more probable. For the supersaturated softer SDS monolayer, the collapse transition is initiated by the buckling of monolayers, followed primarily by budding and detachment of the nanoscale swollen micelle from the monolayer. Despite a number of extensive studies of monolayer collapse at the air/water interface, to our knowledge the conversion of surfactants from the liquid-liquid interface to swollen micellar aggregates as described here has not been reported in the literature. PMID:20420404

Shi, Wen-Xiong; Guo, Hong-Xia

2010-05-20

299

Rapid Discrimination of Gram-Positive and Gram-Negative Bacteria in Liquid Samples by Using NaOH-Sodium Dodecyl Sulfate Solution and Flow Cytometry  

PubMed Central

Background For precise diagnosis of urinary tract infections (UTI), and selection of the appropriate prescriptions for their treatment, we explored a simple and rapid method of discriminating gram-positive and gram-negative bacteria in liquid samples. Methodology/Principal Findings We employed the NaOH-sodium dodecyl sulfate (SDS) solution conventionally used for plasmid extraction from Escherichia coli and the automated urine particle analyzer UF-1000i (Sysmex Corporation) for our novel method. The NaOH-SDS solution was used to determine differences in the cell wall structures between gram-positive and gram-negative bacteria, since the tolerance to such chemicals reflects the thickness and structural differences of bacterial cell walls. The UF-1000i instrument was used as a quantitative bacterial counter. We found that gram-negative bacteria, including E. coli, in liquid culture could easily be lysed by direct addition of equal volumes of NaOH-SDS solution. In contrast, Enterococcus faecalis, which is a gram-positive bacterium, could not be completely lysed by the solution. We then optimized the reaction time of the NaOH-SDS treatment at room temperature by using 3 gram-positive and 4 gram-negative bacterial strains and determined that the optimum reaction time was 5 min. Finally, in order to evaluate the generalizability of this method, we treated 8 gram-positive strains and 8 gram-negative strains, or 4 gram-positive and 4 gram-negative strains incubated in voluntary urine from healthy volunteers in the same way and demonstrated that all the gram-positive bacteria were discriminated quantitatively from gram negative bacteria using this method. Conclusions/Significance Using our new method, we could easily discriminate gram-positive and gram-negative bacteria in liquid culture media within 10 min. This simple and rapid method may be useful for determining the treatment course of patients with UTIs, especially for those without a prior history of UTIs. The method may be easily applied in order to obtain additional information for clinical prescriptions from bacteriuria. PMID:23077549

Wada, Atsushi; Kono, Mari; Kawauchi, Sawako; Takagi, Yuri; Morikawa, Takashi; Funakoshi, Kunihiro

2012-01-01

300

Effects of Selenium on Colon Carcinogenesis Induced by Azoxymethane and Dextran Sodium Sulfate in Mouse Model with High-Iron Diet  

PubMed Central

Selenium (Se) is known to prevent several cancers while the relationship between high iron and the risk of colorectal cancer is controversial. To investigate the effects of Se in colon carcinogenesis, we subjected three different levels of Se and high-iron diet to a mouse model of colon cancer in which animals were treated with three azoxymethane (AOM) injections followed by dextran sodium sulfate (DSS) administration. There were five experimental groups including vehicle group [normal-Fe (NFe, 45 ppm)+medium-Se (MSe, 0.1 ppm)], positive control group (AOM/DSS+NFe+MSe), AOM/DSS+high-Fe (HFe, 450 ppm)+low-Se (LSe, 0.02 ppm), AOM/DSS+HFe+MSe, and AOM/DSS+HFe+high-Se (HSe, 0.5 ppm). The animals were fed on the three different Se diets for 24 weeks. The incidence of colon tumor in the high-Se diet group (AOM/DSS+HFe+HSe) showed 19.4% lower than positive control group, 5.9% lower than AOM/DSS+HFe+MSe diet group, and 11.1% lower than AOM/DSS+HFe+LSe group. The tumor multiplicity was significantly higher in the low-Se diet group (AOM/DSS+HFe+LSe) compare to all other AOM/DSS treated groups. In the high-Se diet group, the activity of hepatic GPx was comparable to that of positive control group, and significantly higher than those of low-Se or medium-Se diet groups. Expression level of hepatic GPx-1 showed similar results. Hepatic malondialdehyde (MDA) level (indicator of oxidative stress) in the low-Se diet group showed the highest compared to the other groups, and it was significantly higher than positive control group. In the high-Se diet group the level of MDA in the liver was significantly lower than all other AOM/DSS treated groups. High-Se diet group showed significantly lower proliferative index than low-Se and medium-Se groups. The apoptotic indices in low-Se group and medium-Se group were significantly lower than positive control group. However, apoptotic index of high-Se diet group was significantly higher than all other AOM/DSS treated groups. These findings suggest that dietary Se supplement may have protective effect against colon cancer by decreasing proliferation, increasing apoptosis of tumor cells, and reducing oxidative stress in mice with high iron diet. PMID:21826154

Kim, Jun-Hyeong; Hue, Jin-Joo; Kang, Bong Su; Park, Hyunji; Nam, Sang Yoon; Yun, Young Won; Kim, Jong-Soo

2011-01-01

301

Carboxylation and mineralization of m -cresol by a sulfate-reducing bacterial enrichment  

Microsoft Academic Search

An enrichment culture that anaerobically degradedm-cresol under sulfate-reducing conditions was obtained from an anoxic aquifer.m-Cresol removal by the culture was greatest when sulfate or thiosulfate served as electron acceptors; sulfite, nitrate, and CO2 were poor substitutes for sulfate. A14C-labeled carboxylated intermediate was detected when the culture was given14C-labeled bicarbonate and nonlabeledm-cresol or nonlabeled bicarbonate and14C-labeledm-cresol. Metabolism of the carboxylated intermediate

K. Ramanand; Joseph M. Suflita

1993-01-01

302

Novel process of simultaneous removal of SO2 and NO2 by sodium humate solution.  

PubMed

A novel simultaneous flue gas desulfurization and denitrification (FGDD) process using sodium humate (HA-Na) solution was proposed. This study relates to the SO2/NO2 absorption efficiency and products of simultaneous removing SO2 and NO2 in a bubbling reactor, especially the effect of recycled water on the SO2/NO2 absorption. Under alkaline conditions, the sulfate content in S-containing compound decreases with the increase of NO2 concentration, whereas there is a contrary result under acidic conditions. Whether the absorption liquid is alkaline or acidic, the presence of NO2 improves the SO2 absorption into HA-Na solution, because NO2 may promote the oxidation of sulfite to sulfate. It seems that the presence of SO2 is unfavorable for the NO2 absorption, but the NO2 absorption efficiency can be improved with the cycle number rising due to the increasing amount of sulfite. Although all the ion concentrations of Na+,SO4(2-),SO3(2-), and NO3- have a gradual increase as the cycle number rises, the ion concentrations of SO4(2-) and Na+ are far more than that of the other ions, which results in a slight decrease of the SO2 absorption efficiency. However, the initial pH of HA-Na solution prepared by recycled water decreases from 10 to 8.1 with the cycle number increasing from 1 to 10, whereas the final pH (the pH after absorption reaction is finished) remains almost constant (3.3). The SO2 absorption efficiency is above 98% and the NO2 absorption efficiency may reach above 95% in the optimal condition in this process. The chief byproduct is a compound fertilizer consisting of humic acid (HA), sulfate, and nitrate. PMID:20704283

Hu, Guoxin; Sun, Zhiguo; Gao, Hanyang

2010-09-01

303

21 CFR 184.1721 - Sodium acetate.  

Code of Federal Regulations, 2013 CFR

...anhydrous or trihydrated form. It is produced synthetically by the neutralization of acetic acid with sodium carbonate or by treating calcium acetate with sodium sulfate and sodium bicarbonate. (b) The ingredient meets the...

2013-04-01

304

21 CFR 184.1721 - Sodium acetate.  

...anhydrous or trihydrated form. It is produced synthetically by the neutralization of acetic acid with sodium carbonate or by treating calcium acetate with sodium sulfate and sodium bicarbonate. (b) The ingredient meets the...

2014-04-01

305

21 CFR 184.1721 - Sodium acetate.  

Code of Federal Regulations, 2012 CFR

...anhydrous or trihydrated form. It is produced synthetically by the neutralization of acetic acid with sodium carbonate or by treating calcium acetate with sodium sulfate and sodium bicarbonate. (b) The ingredient meets the...

2012-04-01

306

21 CFR 184.1721 - Sodium acetate.  

Code of Federal Regulations, 2011 CFR

...anhydrous or trihydrated form. It is produced synthetically by the neutralization of acetic acid with sodium carbonate or by treating calcium acetate with sodium sulfate and sodium bicarbonate. (b) The ingredient meets the...

2011-04-01

307

21 CFR 184.1721 - Sodium acetate.  

Code of Federal Regulations, 2010 CFR

...anhydrous or trihydrated form. It is produced synthetically by the neutralization of acetic acid with sodium carbonate or by treating calcium acetate with sodium sulfate and sodium bicarbonate. (b) The ingredient meets the...

2010-04-01

308

Macrokinetics of magnesium sulfite oxidation inhibited by ascorbic acid.  

PubMed

Magnesia flue gas desulfurization is a promising process for small to medium scale industrial coal-fired boilers in order to reduce sulfur dioxide emissions, in which oxidation control of magnesium sulfite is of great importance for the recycling of products. Effects of four inhibitors were compared by kinetic experiments indicating that ascorbic acid is the best additive, which retards the oxidation process of magnesium sulfite in trace presence. The macrokinetics of magnesium sulfite oxidation inhibited by ascorbic acid were studied. Effects of the factors, including ascorbic acid concentration, magnesium sulfite concentration, oxygen partial pressure, pH, and temperature, were investigated in a stirred reactor with bubbling. The results show that the reaction rate is -0.55 order in ascorbic acid, 0.77 in oxygen partial pressure, and zero in magnesium sulfite concentration, respectively. The apparent activation energy is 88.0 kJ mol(-1). Integrated with the kinetic model, it is concluded that the oxidation rate of magnesium sulfite inhibited by ascorbic acid is controlled by the intrinsic chemical reaction. The result provides a useful reference for sulfite recovery in magnesia desulfurization. PMID:23692683

Lidong, Wang; Yongliang, Ma; Wendi, Zhang; Qiangwei, Li; Yi, Zhao; Zhanchao, Zhang

2013-08-15

309

Chemically induced unfolding of bovine serum albumin by urea and sodium dodecyl sulfate: a spectral study with the polarity-sensitive charge-transfer fluorescent probe (E)-3-(4-methylaminophenyl)acrylic acid methyl ester.  

PubMed

Sensitivity of the charge-transfer (CT) band of the fluorescence probe (E)-3-(4-methylaminophenyl)acrylic acid methyl ester (MAPAME) towards the polarity of its immediate environment is employed to investigate the binding interaction of the probe with bovine serum albumin (BSA) and uncoiling of BSA by the denaturants urea and sodium dodecyl sulfate micelles. Binding of the probe with BSA produces a blue shift and enhanced intensity of the CT emission band which clearly point toward a decrease in polarity of the immediate environment of MAPAME. This is expected, since binding with BSA moves the probe from a polar water environment to a much less polar, hydrophobic protein interior, where the CT band is expected to be blue-shifted. Higher intensity arises due to fewer non-radiative decay paths available to the probe in the hydrophobic protein environment. Chemically induced unfolding of BSA by urea and sodium dodecyl sulfate is tracked by monitoring the induced spectral changes of the protein-bound probe MAPAME. Red-edge excitation shift or REES, fluorescence resonance energy transfer (FRET) and anisotropy measurements are used to investigate and monitor these binding and unfolding processes. PMID:19466702

Ghosh, Shalini; Guchhait, Nikhil

2009-07-13

310

Differences in the binding of sulfate, selenate and thiosulfate ions to bovine liver rhodanese, and a description of a binding site for ammonium and sodium ions. An X-ray diffraction study.  

PubMed

The binding of sulfate, selenate and thiosulfate by the sulfur-transferase rhodanese (EC 2.8.1.1) in the crystalline state has been studied by X-ray analysis at resolutions between 0.23 nm and 0.4 nm. The three ions appear to occupy a common site between the N eta atoms of Arg-29 and the main-chain NH group of Glu-148 at the surface of the enzyme molecule. A second binding site for the three ions is situated at the entrance to the active centre, between the side chains of Arg-186 and Lys-249. Selenate and thiosulfate are bound equally well at both anion-binding sites. Sulfate, however, binds better at the first position, near Arg-29, than at the second site near Arg-186. In the complex of sulfur-rhodanese with thiosulfate, the outer sulfur atom of the anion near the active centre points towards the extra sulfur atom which is bound as a persulfide to the S gamma of the essential Cys-247. The distance between the outer sulfur atom of the thiosulfate ion and the persulfide sulfur atom appears to be about 0.3 nm. The thiosulfate difference Fourier also shows a distinct, localized conformational change involving residues 71, 72 and 249. This is the result of the replacement of an ammonium ion in the sulfate and selenate media by a sodium ion in the sodium thiosulfate solution. Rhodanese is apparently able to accomodate ions with different radii at this cation-binding site by minor structural alterations. PMID:6589161

Lijk, L J; Torfs, C A; Kalk, K H; De Maeyer, M C; Hol, W G

1984-07-16

311

The octaheme SirA catalyses dissimilatory sulfite reduction in Shewanella oneidensis MR-1  

SciTech Connect

Shewanella oneidensis MR-1 is a metal reducer that uses a large number of electron acceptors that include thiosulfate, polysulfide, and sulfite. The enzyme required for thiosulfate and polysulfide respiration has been recently identified, but the mechanisms of sulfite reduction remained unexplored. Analysis of MR-1 cultures grown anaerobically with sulfite suggested that the dissimilatory sulfite reductase catalyzes six-electron reduction of sulfite to sulfide. Reduction of sulfite required menaquinones and c cytochromes but appeared to be independent of the intermediate electron carrier CymA. Furthermore, the terminal sulfite reductase, SirA, was identified as an octaheme c cytochrome with an atypical heme binding site that represents a new class of sulfite reductases. The sirA locus was identified in the genomes of several sequenced Shewanella genomes, and its presence appears to be linked to the ability of these organisms to reduce sulfite under anaerobic conditions.

Shirodkar, Sheetal; Reed, Samantha B.; Romine, Margaret F.; Saffarini, Daad

2011-01-01

312

Evaluation of microbial diversity in sulfite-added and sulfite-free wine by culture-dependent and -independent methods.  

PubMed

The difference in microbiota including non-lactic acid bacteria, non-acetic acid bacteria, and wild yeast during winemaking and in the end-products between sulfite-added and sulfite-free wine, was investigated using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and a culture-dependent method. There were differences between the microorganisms detected by PCR-DGGE and those detected by the culture-dependent method, probably because of the selectivity of culture medium and the characteristics of PCR-based method. In both the red wine and white wine, the microbial diversity of the sulfite-added wine was lower than that of the sulfite-free wine during fermentation. Tatumella terrea was detected from the fermenting must by PCR-DGGE and by the culture-dependent method, even though sulfite inhibited its growth to some extent. We confirmed that the addition of sulfite plays an important role in winemaking by inhibiting the growth of unexpected microorganisms, but on the other hand, it was revealed that some microorganisms can survive and grow in sulfite-added fermenting must. We also analyzed 15 samples of commercial wines by the PCR-DGGE method and detected various microorganisms. Among them, Sphingomonas sp., Pseudozyma sp., Ochromonas sp. and Methylophilus sp. were found for the first time in wine as far as we know. We did not identify a specific microorganism that was detected only from wines without sulfite addition. Thus, the microbiota of end-products seemed to be influenced by other factors, such as filtration before bottling, the production equipment and the storage environment. PMID:24239025

Takahashi, Masayuki; Ohta, Tami; Masaki, Kazuo; Mizuno, Akihiro; Goto-Yamamoto, Nami

2014-05-01

313

Electrocatalytic sulfite biosensor with human sulfite oxidase co-immobilized with cytochrome c in a polyelectrolyte-containing multilayer.  

PubMed

An efficient electrocatalytic biosensor for sulfite detection was developed by co-immobilizing sulfite oxidase and cytochrome c with polyaniline sulfonic acid in a layer-by-layer assembly. QCM, UV-Vis spectroscopy and cyclic voltammetry revealed increasing loading of electrochemically active protein with the formation of multilayers. The sensor operates reagentless at low working potential. A catalytic oxidation current was detected in the presence of sulfite at the modified gold electrode, polarized at +0.1 V (vs. Ag/AgCl 1 M KCl). The stability of the biosensor performance was characterized and optimized. A 17-bilayer electrode has a linear range between 1 and 60 microM sulfite with a sensitivity of 2.19 mA M(-1) sulfite and a response time of 2 min. The electrode retained a stable response for 3 days with a serial reproducibility of 3.8% and lost 20% of sensitivity after 5 days of operation. It is possible to store the sensor in a dry state for more than 2 months. The multilayer electrode was used for determination of sulfite in unspiked and spiked samples of red and white wine. The recovery and the specificity of the signals were evaluated for each sample. PMID:18932024

Spricigo, Roberto; Dronov, Roman; Lisdat, Fred; Leimkühler, Silke; Scheller, Frieder W; Wollenberger, Ulla

2009-01-01

314

TREATMENT OF HEXAVALENT CHROMIUM IN CHROMITE ORE PROCESSING SOLID WASTE USING A MIXED REDUCTANT SOLUTION OF FERROUS SULFATE AND SODIUM DITHIONITE  

EPA Science Inventory

We developed a method for disseminating ferrous iron in the subsurface to enhance chemical reduction of hexavalent chromium (Cr(VI)) in a chromite ore processing solid waste derived from the production of ferrochrome alloy. The method utilizes ferrous sulfate (FeSO4) in combinati...

315

Evaluation of Sodium Bicarbonate, Chloride, or Sulfate with a Coccidiostat in Corn-Soy or Corn-Soy-Meat Diets for Broiler Chickens  

Microsoft Academic Search

During the period from January to June, combined-sex broiler chickens were inoculated with coc- cidia via drinking water at 14 d of age. In a completely randomized design (eight replicate pens; 88 chicks per pen) using built-up litter, experimental diets contained monensin plus 0.20% dietary sodium bicarbonate (SBC), which provided 0.054% sodium and 0.144% bicarbonate. Treatment with SBC significantly improved

D. M. HOOGE; K. R. CUMMINGS; J. L. McNAUGHTON

316

Linkage of High Rates of Sulfate Reduction in Yellowstone Hot Springs to Unique Sequence Types in the Dissimilatory Sulfate Respiration Pathway  

Microsoft Academic Search

Diversity, habitat range, and activities of sulfate-reducing prokaryotes within hot springs in Yellowstone National Park were characterized using endogenous activity measurements, molecular characterization, and enrichment. Five major phylogenetic groups were identified using PCR amplification of the dissimilatory sulfite reductase genes (dsrAB) from springs demonstrating significant sulfate reduction rates, including a warm, acidic (pH 2.5) stream and several nearly neutral hot

Susan Fishbain; Jesse G. Dillon; Heidi L. Gough; David A. Stahl

2003-01-01

317

Revisiting the dissimilatory sulfate reduction pathway.  

PubMed

Sulfur isotopes in the geological record integrate a combination of biological and diagenetic influences, but a key control on the ratio of sulfur isotopes in sedimentary materials is the magnitude of isotope fractionation imparted during dissimilatory sulfate reduction. This fractionation is controlled by the flux of sulfur through the network of chemical reactions involved in sulfate reduction and by the isotope effect associated with each of these chemical reactions. Despite its importance, the network of reactions constituting sulfate reduction is not fully understood, with two principle networks underpinning most isotope models. In this study, we build on biochemical data and recently solved crystal structures of enzymes to propose a revised network topology for the flow of sulfur through the sulfate reduction metabolism. This network is highly branched and under certain conditions produces results consistent with the observations that motivated previous sulfate reduction models. Our revised network suggests that there are two main paths to sulfide production: one that involves the production of thionate intermediates, and one that does not. We suggest that a key factor in determining sulfur isotope fractionation associated with sulfate reduction is the ratio of the rate at which electrons are supplied to subunits of Dsr vs. the rate of sulfite delivery to the active site of Dsr. This reaction network may help geochemists to better understand the relationship between the physiology of sulfate reduction and the isotopic record it produces. PMID:21884365

Bradley, A S; Leavitt, W D; Johnston, D T

2011-09-01

318

Identification of Bacillus subtilis CysL, a regulator of the cysJI operon, which encodes sulfite reductase.  

PubMed

The way in which the genes involved in cysteine biosynthesis are regulated is poorly characterized in Bacillus subtilis. We showed that CysL (formerly YwfK), a LysR-type transcriptional regulator, activates the transcription of the cysJI operon, which encodes sulfite reductase. We demonstrated that a cysL mutant and a cysJI mutant have similar phenotypes. Both are unable to grow using sulfate or sulfite as the sulfur source. The level of expression of the cysJI operon is higher in the presence of sulfate, sulfite, or thiosulfate than in the presence of cysteine. Conversely, the transcription of the cysH and cysK genes is not regulated by these sulfur sources. In the presence of thiosulfate, the expression of the cysJI operon was reduced 11-fold, whereas the expression of the cysH and cysK genes was increased, in a cysL mutant. A cis-acting DNA sequence located upstream of the transcriptional start site of the cysJI operon (positions -76 to -70) was shown to be necessary for sulfur source- and CysL-dependent regulation. CysL also negatively regulates its own transcription, a common characteristic of the LysR-type regulators. Gel mobility shift assays and DNase I footprint experiments showed that the CysL protein specifically binds to cysJ and cysL promoter regions. This is the first report of a regulator of some of the genes involved in cysteine biosynthesis in B. subtilis. PMID:12169591

Guillouard, Isabelle; Auger, Sandrine; Hullo, Marie-Françoise; Chetouani, Farid; Danchin, Antoine; Martin-Verstraete, Isabelle

2002-09-01

319

Identification of Bacillus subtilis CysL, a Regulator of the cysJI Operon, Which Encodes Sulfite Reductase  

PubMed Central

The way in which the genes involved in cysteine biosynthesis are regulated is poorly characterized in Bacillus subtilis. We showed that CysL (formerly YwfK), a LysR-type transcriptional regulator, activates the transcription of the cysJI operon, which encodes sulfite reductase. We demonstrated that a cysL mutant and a cysJI mutant have similar phenotypes. Both are unable to grow using sulfate or sulfite as the sulfur source. The level of expression of the cysJI operon is higher in the presence of sulfate, sulfite, or thiosulfate than in the presence of cysteine. Conversely, the transcription of the cysH and cysK genes is not regulated by these sulfur sources. In the presence of thiosulfate, the expression of the cysJI operon was reduced 11-fold, whereas the expression of the cysH and cysK genes was increased, in a cysL mutant. A cis-acting DNA sequence located upstream of the transcriptional start site of the cysJI operon (positions ?76 to ?70) was shown to be necessary for sulfur source- and CysL-dependent regulation. CysL also negatively regulates its own transcription, a common characteristic of the LysR-type regulators. Gel mobility shift assays and DNase I footprint experiments showed that the CysL protein specifically binds to cysJ and cysL promoter regions. This is the first report of a regulator of some of the genes involved in cysteine biosynthesis in B. subtilis. PMID:12169591

Guillouard, Isabelle; Auger, Sandrine; Hullo, Marie-Francoise; Chetouani, Farid; Danchin, Antoine; Martin-Verstraete, Isabelle

2002-01-01

320

21 CFR 201.22 - Prescription drugs containing sulfites; required warning statements.  

Code of Federal Regulations, 2012 CFR

... 2012-04-01 false Prescription drugs containing sulfites; required...Labeling Provisions § 201.22 Prescription drugs containing sulfites; required...asthmatics. The labeling for any prescription drug product to which...

2012-04-01

321

A Revised Isotope Fractionation Model for Dissimilatory Sulfate Reduction in Sulfate Reducing Bacteria  

NASA Astrophysics Data System (ADS)

Sulfur isotope fractionation during dissimilatory sulfate reduction is related to the stepwise reduction of sulfate to sulfide within the cells of the bacteria. The magnitude of fractionation is dependent on the interplay between different reduction steps in a chain of reactions. One of the most intriguing questions in sulfur isotope geochemistry stems from the observation that in natural environments, sulfides are commonly depleted in 34S by -45\\permil to -70\\permil relative to sulfate whereas maximum sulfur isotope difference between produced sulfides and sulfate of around -46\\permil have been obtained in laboratory cultures. A maximum fractionation of 47\\permil was also predicted by the model of sulfate reduction introduced by Rees (1973). The Rees model is commonly accepted but since its introduction, new information about sulfate reduction and isotope fractionation processes has become available in the literature that demands an update of some of its assumptions. We present a improved model for bacterial sulfate reduction which includes revised fractionation factors for the sulfite-sulfide step, a multi-step reduction of sulfite to sulfide including reverse flows and an exchange flux of sulfide between the cell and ambient water. With this model we show that, contrary to the model of Rees (1973), isotope fractionations well in excess of -47\\permil are possible. Therefore, some of the large sulfur isotope fractionations observed in nature may be explained without the need of alternate pathways involving the oxidative sulfur cycle as proposed by Canfield and Thamdrup (1994). In particular, we speculate that large fractionations should occur under hypersulfidic conditions and substrate limitation. We obviously do not disregard the involvement of processes related to the oxidative cycle of sulfur in near-surface environments, but our model suggests that this is not a prerequisite condition to obtain large isotope fractionations. References: Canfield D. E. and Thamdrup B. (1994) Science, 266, 1973-1975. Rees (1973) Geochimica et Cosmochimica Acta, 37, 1141-1162

Benjamin, B.; Bernasconi, S. M.

2004-12-01

322

An enzyme-linked immunosorbent assay for detection of antibodies to maedi-visna virus in sheep. I. A simple technique for production of antigen using sodium dodecyl sulfate treatment.  

PubMed

We report the efficacy of an anionic detergent, sodium dodecyl sulfate (SDS) for preparing maedi-visna antigens for an indirect enzyme-linked immunosorbent assay (i-ELISA). Ovine maedi-visna virus (MVV) pelleted by differential centrifugation followed by liquid chromatography was treated with SDS or one of three lipid solvents: ethyl ether, chloroform or fluorocarbon. The SDS-treated antigen resulted in higher optical density values with positive serum and better discrimination between positive and negative serum samples from specific-pathogen-free (SPF) sheep experimentally inoculated with the virus. Optimal results were obtained when MVV was treated with concentrations of 0.25% and 0.125% of SDS. A viral antigen prepared by centrifugation and treatment of a viral pellet with SDS was also suitable for the i-ELISA. This latter technique may facilitate the production of MVV antigens for use in the i-ELISA. PMID:2174295

Simard, C L; Briscoe, M R

1990-10-01

323

Coupled sulfur and oxygen isotope insight into bacterial sulfate reduction in the natural environment  

NASA Astrophysics Data System (ADS)

We present new sulfur and oxygen isotope data in sulfate (?34SSO4 and ?18OSO4, respectively), from globally distributed marine and estuary pore fluids. We use this data with a model of the biochemical steps involved in bacterial sulfate reduction (BSR) to explore how the slope on a ?18OSO4 vs. ?34SSO4 plot relates to the net sulfate reduction rate (nSRR) across a diverse range of natural environments. Our data demonstrate a correlation between the nSRR and the slope of the relative evolution of oxygen and sulfur isotopes (?18OSO4 vs. ?34SSO4) in the residual sulfate pool, such that higher nSRR results in a lower slope (sulfur isotopes increase faster relative to oxygen isotopes). We combine these results with previously published literature data to show that this correlation scales over many orders of magnitude of nSRR. Our model of the mechanism of BSR indicates that the critical parameter for the relative evolution of oxygen and sulfur isotopes in sulfate during BSR in natural environments is the rate of intracellular sulfite oxidation. In environments where sulfate reduction is fast, such as estuaries and marginal marine environments, this sulfite reoxidation is minimal, and the ?18OSO4 increases more slowly relative to the ?34SSO4. In contrast, in environments where sulfate reduction is very slow, such as deep sea sediments, our model suggests sulfite reoxidation is far more extensive, with as much as 99% of the sulfate being thus recycled; in these environments the ?18OSO4 increases much more rapidly relative to the ?34SSO4. We speculate that the recycling of sulfite plays a physiological role during BSR, helping maintain microbial activity where the availability of the electron donor (e.g. available organic matter) is low.

Antler, Gilad; Turchyn, Alexandra V.; Rennie, Victoria; Herut, Barak; Sivan, Orit

2013-10-01

324

Desulfosporosinus lacus sp. nov., a sulfate-reducing bacterium isolated from pristine freshwater lake sediments  

Microsoft Academic Search

A novel sulfate-reducing bacterium was isolated from pristine sediments of Lake Stechlin, Germany. This strain, STP12T, was found to contain predominantly c-type cytochromes and to reduce sulfate, sulfite and thiosulfate using lactate as an electron donor. Although STP12T could not utilize elemental sulfur as an electron acceptor, it could support growth by dissimilatory Fe(III) reduction. In a comparison of 16S

S. Ramamoorthy; H. Sass; H. Langner; P. Schumann; R. M. Kroppenstedt; S. Spring; J. Overmann; R. F. Rosenzweig

2006-01-01

325

A revised isotope fractionation model for dissimilatory sulfate reduction in sulfate reducing bacteria  

NASA Astrophysics Data System (ADS)

Sulfur isotope fractionation during dissimilatory sulfate reduction has been conceptually described by the widely accepted Rees model as related to the stepwise reduction of sulfate to sulfide within the cells of bacteria. The magnitude of isotope fractionation is determined by the interplay between different reduction steps in a chain of reactions. Here we present a revision of Rees' model for bacterial sulfate reduction that includes revised fractionation factors for the sulfite-sulfide step and incorporates new forward and reverse steps in the reduction of sulfite to sulfide, as well as exchange of sulfide between the cell and ambient water. With this model we show that in contrast to the Rees model, isotope fractionations well in excess of -46‰ are possible. Therefore, some of the large sulfur isotope fractionations observed in nature can be explained without the need of alternate pathways involving the oxidative sulfur cycle. We use this model to predict that large fractionations should occur under hypersulfidic conditions and where electron acceptor concentrations are limiting.

Brunner, Benjamin; Bernasconi, Stefano M.

2005-10-01

326

Preparation, Characterization, and Selectivity Study of Mixed-Valence Sulfites  

ERIC Educational Resources Information Center

A project involving the synthesis of an isomorphic double sulfite series and characterization by classical inorganic chemical analyses is described. The project is performed by upper-level undergraduate students in the laboratory. This compound series is suitable for examining several chemical concepts and analytical techniques in inorganic…

Silva, Luciana A.; de Andrade, Jailson B.

2010-01-01

327

Clonal mast cell activation syndrome with anaphylaxis to sulfites.  

PubMed

Sulfites are rarely suspected as causative agents of immediate-type hypersensitivity. We report on a 49-year-old male patient who developed recurrent severe hypotension after food ingestion. A diagnosis of monoclonal mast cell activation syndrome was established. In the double-blind, placebo-controlled food challenge, the patient reacted to potassium metabisulfite with anaphylaxis. PMID:23816954

Cifuentes, Liliana; Ring, Johannes; Brockow, Knut

2013-01-01

328

Photoreactions of cyclic sulfite esters: Evidence for diradical intermediates  

PubMed Central

Summary The photochemistry of a phenyl and 1,2-diphenyl substituted sulfite ester is reported. The performance of photoreactions under relatively mild reaction conditions enables the detection of products that have not been observed in previous studies. It is concluded that, complementary to the initially proposed carbene intermediates, diradicals may also be considered. PMID:23019449

Arney, Benny E; Ihmels, Heiko

2012-01-01

329

Sulfite species enhance carbon monoxide release from CO-releasing molecules: implications for the deoxymyoglobin assay of activity.  

PubMed

Carbon monoxide-releasing molecules (CO-RMs) emulate the beneficial (e.g., anti-inflammatory) effects of CO in biology. CO release from CO-RMs is routinely determined in the presence of reduced deoxy-myoglobin by measuring the formation of carboxy-myoglobin (Mb-CO). Previous studies have highlighted discrepancies between the apparent CO release rates of some CO-RMs established using this assay versus other experimental data where a slower or more complex mechanism of release is suggested. It has been hypothesized that some CO-RMs require a CO acceptor, believed to be reduced myoglobin in Mb-CO assays, in order to facilitate the release of CO. Here, we show, for the first time, that CO is not liberated from the ruthenium (Ru)-based [Ru(CO)(3)Cl(2)](2) (CORM-2) and [Ru(CO)(3)Cl(glycinate)] (CORM-3) at an appreciable rate in the presence of reduced myoglobin alone. Rather, we confirm that it is the reducing agent sodium dithionite that facilitates release of CO from these CO-RMs. Other sulfite compounds, namely sodium sulfite and potassium metabisulfite, also promote the liberation of CO from CORM-3. We describe an alternative oxy-hemoglobin assay that eliminates dithionite and suggest that the efficacy of CO-RMs results from intracellular interactions with anions that facilitate CO delivery to therapeutic targets. PMID:22561917

McLean, Samantha; Mann, Brian E; Poole, Robert K

2012-08-01

330

Curcumin, the main part of turmeric, prevents learning and memory changes induced by sodium metabisulfite, a preservative agent, in rats.  

PubMed

Sodium metabisulfite is used as a disinfectant, antioxidant, and preservative agent in the food, beverage, and drug industries. Neurons are highly sensitive to sulfite toxicity. Curcumin is the main part of turmeric and has neuroprotective effects on a variety of nervous system damages. The present study aimed to investigate the possible protective role of curcumin in learning and memory after exposure to sulfite in rats. The rats were divided into five groups receiving distilled water (solvent of the sulfite), olive oil (solvent of the curcumin), sodium metabisulfite (25 mg/kg/day), curcumin (100 mg/kg/day), and sulfite + curcumin. All the animals received daily gavages for 8 weeks. At the end of the 8(th) week, learning and memory were assessed in a partially-baited eight arm radial maze. The animals treated with sulfite showed fewer correct choices and more reference and working memory errors during the learning phase, at the end of the learning phase, and during the retention testing (p<0.001). The study results demonstrated that sulfite-exposure was associated with impaired learning and memory in rats. Adding curcumin to the rat nutrition plays a protective role in learning and memory after exposure to sulfite. PMID:23585719

Noorafshan, Ali; Asadi-Golshan, Reza; Karbalay-Doust, Saied; Abdollahifar, Mohammad Amin; Rashidiani-Rashidabadi, Ali

2013-03-01

331

Disproportionation of inorganic sulfur compounds by the sulfate-reducing bacterium Desulfocapsa thiozymogenes gen. nov., sp. nov  

Microsoft Academic Search

A new strictly anaerobic, gram-negative bacterium was isolated from the sediment of a freshwater lake after enrichment with\\u000a thiosulfate as the energy source. The strain, named Bra2 (DSM 7269), is able to grow by disproportionation of thiosulfate\\u000a or sulfite to sulfate plus sulfide. Elemental sulfur is also disproportionated to sulfate and sulfide, but this only supports\\u000a growth if free sulfide

Peter H. Janssen; Alexandra Schuhmann; Friedhelm Bak; Werner Liesack

1996-01-01

332

Preparation and characterization of sodium dodecyl sulfate doped polypyrrole solid phase micro extraction fiber and its application to endocrine disruptor pesticide analysis.  

PubMed

A robust in house solid-phase micro extraction (SPME) surface has been developed for the headspace (HS)-SPME determination of endocrine disruptor pesticides, namely, Chlorpyrifos, Penconazole, Procymidone, Bromopropylate and Lambda-Cyhalothrin in wine sample by using sodium dodecylsulfate doped polypyrrole SPME fiber. Pyrrole monomer was electrochemically polymerized on a stainless steel wire in laboratory conditions in virtue of diminishing the cost and enhancing the analyte retention on its surface to exert better selectivity and hence the developed polymerized surface could offer to analyst to exploit it as a fiber in headspace SPME analysis. The parameters, mainly, adsorption temperature and time, desorption temperature, stirring rate and salt amount were optimized to be as 70°C and 45min, 200°C, 600rpm and 10gL(-1), respectively. Limit of detection was estimated in the range of 0.073-1.659ngmL(-1) for the pesticides studied. The developed method was applied in to red wine sample with acceptable recovery values (92-107%) which were obtained for these selected pesticides. PMID:23669608

Korba, Korcan; Pelit, Levent; Pelit, Füsun Okçu; Ozdokur, K Volkan; Erta?, Hasan; Ero?lu, Ahmet E; Erta?, F Nil

2013-06-15

333

Effects of ultrasound and sodium lauryl sulfate on the transdermal delivery of hydrophilic permeants: Comparative in vitro studies with full-thickness and split-thickness pig and human skin  

PubMed Central

The simultaneous application of ultrasound and the surfactant sodium lauryl sulfate (referred to as US/SLS) to skin enhances transdermal drug delivery (TDD) in a synergistic mechanical and chemical manner. Since full-thickness skin (FTS) and split-thickness skin (STS) differ in mechanical strength, US/SLS treatment may have different effects on their transdermal transport pathways. Therefore, we evaluated STS as an alternative to the well-established US/SLS-treated FTS model for TDD studies of hydrophilic permeants. We utilized the aqueous porous pathway model to compare the effects of US/SLS treatment on the skin permeability and the pore radius of pig and human FTS and STS over a range of skin electrical resistivity values. Our findings indicate that the US/SLS-treated pig skin models exhibit similar permeabilities and pore radii, but the human skin models do not. Furthermore, the US/SLS-enhanced delivery of gold nanoparticles and quantum dots (two model hydrophilic macromolecules) is greater through pig STS than through pig FTS, due to the presence of less dermis that acts as an artificial barrier to macromolecules. In spite of greater variability in correlations between STS permeability and resistivity, our findings strongly suggest the use of 700-?m-thick pig STS to investigate the in vitro US/SLS-enhanced delivery of hydrophilic macromolecules. PMID:20346994

Seto, Jennifer E.; Polat, Baris E.; Lopez, Renata F.V.; Blankschtein, Daniel; Langer, Robert

2010-01-01

334

Influence of binding of sodium dodecyl sulfate, all-trans-retinol, palmitate, and 8-anilino-1-naphthalenesulfonate on the heat-induced unfolding and aggregation of beta-lactoglobulin B.  

PubMed

Heat treatment of bovine beta-lactoglobulin B (beta-LG) causes it to partially unfold and aggregate via hydrophobic association and intra- and interprotein disulfide bonds. The first stage, which involves a "loosening" of the native structure, is influenced by the environmental conditions, such as pressure, pH, and added solutes. In the present study, four potential beta-LG ligands [palmitate, sodium dodecyl sulfate (SDS), 8-anilino-1-naphthalenesulfonate (ANS), and all-trans-retinol (retinol)] were added to beta-LG solutions prior to heat treatment for 12 min at temperatures between 40 and 93 degrees C. The extent of the changes in secondary and tertiary structures, unfolding, and aggregation at 20 degrees C were determined by circular dichroism, fluorescence, and alkaline- and SDS-polyacrylamide gel electrophoresis (PAGE). Both palmitate and SDS stabilized the native structure of beta-LG against heat-induced structural flexibility, subsequent unfolding, and denaturation. Retinol was less effective, probably because of its lower affinity for the calyx-binding site, and ANS did not stabilize beta-LG, suggesting that ANS did not bind strongly in the calyx. It was also noted that holding a beta-LG solution with added SDS or ANS promoted the formation of a hydrophobically associated non-native dimer. PMID:15826078

Considine, Thérèse; Patel, Hasmukh A; Singh, Harjinder; Creamer, Lawrence K

2005-04-20

335

Simultaneous absorption of mercury and chlorine in sulfite solutions  

Microsoft Academic Search

Simultaneous absorption of mercury (Hg) and chlorine (Cl2) into aqueous sulfite\\/bisulfite (0 to 1mM S(IV)) at pH 4.7 and 5.7 was measured in a wetted wall column. Experiments were performed at ambient temperature and pressure using 5–40ppm Cl2 and 46 ppb Hg. Absorption was modeled using the theory of mass transfer with chemical reaction. At the gas\\/liquid interface, chlorine oxidizes

Sharmistha Roy; Gary T. Rochelle

2004-01-01

336

Oxygen isotopic fractionation during bacterial sulfate reduction  

NASA Astrophysics Data System (ADS)

Sulfur isotope fractionation during bacterial sulfate reduction (BSR) is understood to depend on a variety of environmental parameters, such as sulfate concentration, temperature, cell specific sulfate reduction rates, and the carbon substrate. What controls oxygen isotope fractionation during BSR is less well understood. Some studies have suggested that carbon substrate is important, whereas others concluded that there is a stoichiometric relationship between the fractionations of sulfur and oxygen during BSR. Studies of oxygen fractionation are complicated by isotopic equilibration between sulfur intermediates, particularly sulfite, and water. This process can modify the isotopic composition of the extracellular sulfate pool (?18OSO4 ). Given this, the challenge is to distinguish between this isotopic equilibration and fractionations linked to the kinetic effects of the intercellular enzymes and the incorporation of sulfate into the bacterial cell. The ?18OSO4 , in concert with the sulfur isotope composition of sulfate (?34SSO4), could be a powerful tool for understanding the pathways and environmental controls of BSR in natural systems. We will present ?18OSO4 data measured from batch culture growth of 14 different species of sulfate reducing bacteria for which sulfur isotope data were previously published. A general observation is that ?18OSO4 shows little isotopic change (<4‰) even when the ?34SSO4 varies by up to 30 to 50‰ over the course of the experiment. This disparity could reflect little to no kinetic effect during BSR and/or equilibration between sulfur intermediates and the isotopically light water (~-5‰) of the growth medium. Our present batch culture data do not allow us to convincingly isolate the magnitude and the controlling parameters of the kinetic isotope effect for oxygen. However, ongoing growth of mutant bacteria missing enzymes critical in the different steps of BSR may assist in this mission.

Balci, N.; Turchyn, A. V.; Lyons, T.; Bruchert, V.; Schrag, D. P.; Wall, J.

2006-12-01

337

Determination of sulfite in food by flow injection analysis.  

PubMed

A method is described for the determination of sulfite levels in food products by flow injection analysis (FIA). The method is based on the decolorization of malachite green by SO2, which is isolated from the flowing sample stream by means of a gas diffusion cell. The FIA method has a detection limit in food sample extracts of 0.1 ppm SO2 (3 times peak height of blank), which corresponds to 1-10 ppm SO2 in a food product, depending on the extraction procedure used. At the 5 ppm SO2 level in a food extract, the precision of replicate injections is +/- 1-2%. The method was tested on a variety of both sulfite-treated and untreated food products and the results compared favorably with those obtained by the Monier-Williams, colorimetric (pararosaniline), and enzymatic (sulfite oxidase) methods. The average differences from the FIA results were 19, 11, and 12%, respectively, for those samples (n = 12) above 50 ppm SO2. At lower levels the results were somewhat more erratic due to inaccuracies of the various methods at low concentrations. PMID:3722106

Sullivan, J J; Hollingworth, T A; Wekell, M M; Newton, R T; Larose, J E

1986-01-01

338

Triple-oxygen-isotope determination of molecular oxygen incorporation in sulfate produced during abiotic pyrite oxidation (pH = 2-11)  

NASA Astrophysics Data System (ADS)

Aqueous oxidation of sulfide minerals to sulfate is an integral part of the global sulfur and oxygen cycles. The current model for pyrite oxidation emphasizes the role of Fe 2+-Fe 3+ electron shuttling and repeated nucleophilic attack by water molecules on sulfur. Previous ? 18O-labeled experiments show that a variable fraction (0-60%) of the oxygen in product sulfate is derived from dissolved O 2, the other potential oxidant. This indicates that nucleophilic attack cannot continue all the way to sulfate and that a sulfoxyanion of intermediate oxidation state is released into solution. The observed variability in O 2% may be due to the presence of competing oxidation pathways, variable experimental conditions (e.g. abiotic, biotic, or changing pH value), or uncertainties related to the multiple experiments needed to effectively use the ? 18O label to differentiate sulfate-oxygen sources. To examine the role of O 2 and Fe 3+ in determining the final incorporation of O 2 oxygen in sulfate produced during pyrite oxidation, we designed a set of aerated, abiotic, pH-buffered (pH = 2, 7, 9, 10, and 11), and triple-oxygen-isotope labeled solutions with and without Fe 3+ addition. While abiotic and pH-buffered conditions help to eliminate variables, triple oxygen isotope labeling and Fe 3+ addition help to determine the oxygen sources in sulfate and examine the role of Fe 2+-Fe 3+ electron shuttling during sulfide oxidation, respectively. Our results show that sulfate concentration increased linearly with time and the maximum concentration was achieved at pH 11. At pH 2, 7, and 9, sulfate production was slow but increased by 4× with the addition of Fe 3+. Significant amounts of sulfite and thiosulfate were detected in pH ? 9 reactors, while concentrations were low or undetectable at pH 2 and 7. The triple oxygen isotope data show that at pH ? 9, product sulfate contained 21-24% air O 2 signal, similar to pH 2 with Fe 3+ addition. Sulfate from the pH 2 reactor without Fe 3+ addition and the pH 7 reactors all showed 28-29% O 2 signal. While the O 2% in final sulfate apparently clusters around 25%, the measurable deviations (>experimental error) from the 25% in many reaction conditions suggest that (1) O 2 does get incorporated into intermediate sulfoxyanions (thiosulfate and sulfite) and a fraction survives sulfite-water exchange (e.g. the pH 2 with no Fe 3+ addition and both pH 7 reactors); and (2) direct O 2 oxidation dominates while Fe 3+ shuttling is still competitive in the sulfite-sulfate step (e.g. the pH 9, 10, and 11 and the pH 2 reactor with Fe 3+ addition). Overall, the final sulfate-oxygen source ratio is determined by (1) rate competitions between direct O 2 incorporation and Fe 3+ shuttling during both the formation of sulfite from pyrite and from sulfite to final sulfate, and (2) rate competitions between sulfite and water oxygen exchange and the oxidation of sulfite to sulfate. Our results indicate that thiosulfate or sulfite is the intermediate species released into solution at all investigated pH and point to a set of dynamic and competing fractionation factors and rates, which control the oxygen isotope composition of sulfate derived from pyrite oxidation.

Kohl, Issaku; Bao, Huiming

2011-04-01

339

A light-enhanced metabolism of sulfite in cells of Cucumis sativus L. cotyledons  

Microsoft Academic Search

The effects of light and several photosynthetic inhibitors on the rate of sulfite metabolism in cells obtained from Cucumis sativus L. cotyledons was studied. The cells were treated with 200 µM Na2SO3 and the disappearance of sulfite was monitored using either dithiobisnitrobenzoic acid or fuchsin. The rate of sulfite disappearance in light was double the dark rate. Disalicylidene propanediamine at

B. Rothermel; R. Alscher

1985-01-01

340

Molecular analysis of the metabolic rates of discrete subsurface populations of sulfate reducers.  

PubMed

Elucidating the in situ metabolic activity of phylogenetically diverse populations of sulfate-reducing microorganisms that populate anoxic sedimentary environments is key to understanding subsurface ecology. Previous pure culture studies have demonstrated that the transcript abundance of dissimilatory (bi)sulfite reductase genes is correlated with the sulfate-reducing activity of individual cells. To evaluate whether expression of these genes was diagnostic for subsurface communities, dissimilatory (bi)sulfite reductase gene transcript abundance in phylogenetically distinct sulfate-reducing populations was quantified during a field experiment in which acetate was added to uranium-contaminated groundwater. Analysis of dsrAB sequences prior to the addition of acetate indicated that Desulfobacteraceae, Desulfobulbaceae, and Syntrophaceae-related sulfate reducers were the most abundant. Quantifying dsrB transcripts of the individual populations suggested that Desulfobacteraceae initially had higher dsrB transcripts per cell than Desulfobulbaceae or Syntrophaceae populations and that the activity of Desulfobacteraceae increased further when the metabolism of dissimilatory metal reducers competing for the added acetate declined. In contrast, dsrB transcript abundance in Desulfobulbaceae and Syntrophaceae remained relatively constant, suggesting a lack of stimulation by added acetate. The indication of higher sulfate-reducing activity in the Desulfobacteraceae was consistent with the finding that Desulfobacteraceae became the predominant component of the sulfate-reducing community. Discontinuing acetate additions resulted in a decline in dsrB transcript abundance in the Desulfobacteraceae. These results suggest that monitoring transcripts of dissimilatory (bi)sulfite reductase genes in distinct populations of sulfate reducers can provide insight into the relative rates of metabolism of different components of the sulfate-reducing community and their ability to respond to environmental perturbations. PMID:21764959

Miletto, M; Williams, K H; N'Guessan, A L; Lovley, D R

2011-09-01

341

Molecular Analysis of the Metabolic Rates of Discrete Subsurface Populations of Sulfate Reducers?  

PubMed Central

Elucidating the in situ metabolic activity of phylogenetically diverse populations of sulfate-reducing microorganisms that populate anoxic sedimentary environments is key to understanding subsurface ecology. Previous pure culture studies have demonstrated that the transcript abundance of dissimilatory (bi)sulfite reductase genes is correlated with the sulfate-reducing activity of individual cells. To evaluate whether expression of these genes was diagnostic for subsurface communities, dissimilatory (bi)sulfite reductase gene transcript abundance in phylogenetically distinct sulfate-reducing populations was quantified during a field experiment in which acetate was added to uranium-contaminated groundwater. Analysis of dsrAB sequences prior to the addition of acetate indicated that Desulfobacteraceae, Desulfobulbaceae, and Syntrophaceae-related sulfate reducers were the most abundant. Quantifying dsrB transcripts of the individual populations suggested that Desulfobacteraceae initially had higher dsrB transcripts per cell than Desulfobulbaceae or Syntrophaceae populations and that the activity of Desulfobacteraceae increased further when the metabolism of dissimilatory metal reducers competing for the added acetate declined. In contrast, dsrB transcript abundance in Desulfobulbaceae and Syntrophaceae remained relatively constant, suggesting a lack of stimulation by added acetate. The indication of higher sulfate-reducing activity in the Desulfobacteraceae was consistent with the finding that Desulfobacteraceae became the predominant component of the sulfate-reducing community. Discontinuing acetate additions resulted in a decline in dsrB transcript abundance in the Desulfobacteraceae. These results suggest that monitoring transcripts of dissimilatory (bi)sulfite reductase genes in distinct populations of sulfate reducers can provide insight into the relative rates of metabolism of different components of the sulfate-reducing community and their ability to respond to environmental perturbations. PMID:21764959

Miletto, M.; Williams, K. H.; N'Guessan, A. L.; Lovley, D. R.

2011-01-01

342

Molecular analysis of the metabolic rates of discrete subsurface populations of sulfate reducers  

SciTech Connect

Elucidating the in situ metabolic activity of phylogenetically diverse populations of sulfate-reducing microorganisms that populate anoxic sedimentary environments is key to understanding subsurface ecology. Previous pure culture studies have demonstrated that transcript abundance of dissimilatory (bi)sulfite reductase genes is correlated with the sulfate reducing activity of individual cells. To evaluate whether expression of these genes was diagnostic for subsurface communities, dissimilatory (bi)sulfite reductase gene transcript abundance in phylogenetically distinct sulfate-reducing populations was quantified during a field experiment in which acetate was added to uranium-contaminated groundwater. Analysis of dsrAB sequences prior to the addition of acetate indicated that Desulfobacteraceae, Desulfobulbaceae, and Syntrophaceae-related sulfate reducers were the most abundant. Quantifying dsrB transcripts of the individual populations suggested that Desulfobacteraceae initially had higher dsrB transcripts per cell than Desulfobulbaceae or Syntrophaceae populations, and that the activity of Desulfobacteraceae increased further when the metabolism of dissimilatory metal reducers competing for the added acetate declined. In contrast, dsrB transcript abundance in Desulfobulbaceae and Syntrophaceae remained relatively constant, suggesting a lack of stimulation by added acetate. The indication of higher sulfate-reducing activity in the Desulfobacteraceae was consistent with the finding that Desulfobacteraceae became the predominant component of the sulfate-reducing community. Discontinuing acetate additions resulted in a decline in dsrB transcript abundance in the Desulfobacteraceae. These results suggest that monitoring transcripts of dissimilatory (bi)sulfite reductase genes in distinct populations of sulfate reducers can provide insight into the relative rates of metabolism of different components of the sulfate-reducing community and their ability to respond to environmental perturbations.

Miletto, M.; Williams, K.H.; N'Guessan, A.L.; Lovley, D.R.

2011-04-01

343

The effect of cooking preparations on the residual sulfite concentrations in shrimp  

E-print Network

when shrimp was boiled shell-off. During the first minute, 25. 9$ of the original concentration was lost and a total loss of 40. 6$ was observed after five minutes of cooking time. This is most probably due to the removal of the shel 1 prior... Range Test f' or Residual Sulfite in Shrimp as a Function of Preparation Time Cooking Procedure Time (min) Boiled Shel 1-on (sulfite ppm) Boiled Shell-off (sulfite ppm) Breaded Deep Fried (sulf'ite ppm) 0 ? 1 0-2 0-3 0-4 0-5 96 ' 5 b 61. 6...

Lally, Audrey Ann

2012-06-07

344

Barium Sulfate  

MedlinePLUS

... uses a computer to put together x-ray images to create cross-sectional or three dimensional pictures of the inside of the body). Barium sulfate is in a class of medications called radiopaque contrast media. It works by coating the esophagus, stomach, or ...

345

A Continuous Spectrophotometric Assay for APS Reductase Activity with Sulfite-Selective Probes  

PubMed Central

Mycobacterium tuberculosis (Mtb) adenosine 5?-phosphosulfate (APS) reductase (EC number 1.8.4.10), (APR) catalyzes the first committed step in sulfate reduction for the biosynthesis of essential reduced sulfur-containing biomolecules, such as cysteine, and is essential for survival in the latent phase of TB infection. Despite the importance of APR to Mtb, and other bacterial pathogens, current assay methods depend on use of [35S]-labeled APS or shunt AMP to a coupled-enzyme system. Both methods are cumbersome and require the use of expensive reagents. Here we report the development of a continuous spectrophotometric method for measuring APR activity by using novel sulfite-selective colorimetric or “off-on” fluorescent levulinate-based probes. The APR activity can thus be followed by monitoring the increase in absorbance or fluorescence of the resulting phenolate product. Using this assay, we determined Michelis-Menten kinetic constants (Km, kcat, kcat/Km) and apparent inhibition constant (Ki) for adenosine 5?-diphosphate (ADP), which compared favorably to values obtained in the gold-standard radioactive assay. The newly developed assay is robust and easy to perform with a simple spectrophotometer. PMID:23711725

Paritala, Hanumantharao; Carroll, Kate S.

2013-01-01

346

Curcumin Can Prevent the Changes in Cerebellar Structure and Function Induced by Sodium Metabisulfite in Rat  

PubMed Central

Sulfites are used as anti-microbial and anti-oxidant agents in the food and pharmaceutical industries. Curcumin, a flavonoid, is an Asian spice that shows neuroprotective activities. The current study aimed to stereologically assess the rats' cerebellar cortex and rotarod performance following sulfite exposure and determine the possible neuroprotective potential of curcumin. The rats were divided into five groups: distilled water, olive oil, curcumin (100 mg/kg/day), sodium metabisulfite (25 mg/kg/day), and sodium metabisulfite+curcumin. At 56 days after treatment, rotarod performance was tested, and then the cerebellum was removed for stereological analysis. The study results revealed 31%, 36%, 19% and 24% decrease in the total volume of the cerebellum, cortex, the total number of the Purkinje cells and length of the nerve fibers in the cortex per Purkinje, respectively in the sodium metabisulfite-treated rats compared to the distilled water group (p<0.01). The pre-trained animals on the rotarod apparatus were tested first on the fixed speed rotarod protocol followed by the accelerating rotarod protocol two days later. The results showed a significant decrease in the latency to fall in both test in sulfite-treated rats. The sulfite effects on the structural parameters and rotarod performance were significantly protected by the concomitant curcumin treatment (p<0.001). Sulfite can induce structural and functional changes in the rats' cerebellum and concomitant curcumin prescription plays a neuroprotective role. PMID:24465141

Noorafshan, Ali; Rashidiani-Rashidabadi, Ali; Poostpasand, Aghdas; Abdollahifar, Mohammad-Amin; Asadi-Golshan, Reza

2013-01-01

347

Curcumin can prevent the changes in cerebellar structure and function induced by sodium metabisulfite in rat.  

PubMed

Sulfites are used as anti-microbial and anti-oxidant agents in the food and pharmaceutical industries. Curcumin, a flavonoid, is an Asian spice that shows neuroprotective activities. The current study aimed to stereologically assess the rats' cerebellar cortex and rotarod performance following sulfite exposure and determine the possible neuroprotective potential of curcumin. The rats were divided into five groups: distilled water, olive oil, curcumin (100 mg/kg/day), sodium metabisulfite (25 mg/kg/day), and sodium metabisulfite+curcumin. At 56 days after treatment, rotarod performance was tested, and then the cerebellum was removed for stereological analysis. The study results revealed 31%, 36%, 19% and 24% decrease in the total volume of the cerebellum, cortex, the total number of the Purkinje cells and length of the nerve fibers in the cortex per Purkinje, respectively in the sodium metabisulfite-treated rats compared to the distilled water group (p<0.01). The pre-trained animals on the rotarod apparatus were tested first on the fixed speed rotarod protocol followed by the accelerating rotarod protocol two days later. The results showed a significant decrease in the latency to fall in both test in sulfite-treated rats. The sulfite effects on the structural parameters and rotarod performance were significantly protected by the concomitant curcumin treatment (p<0.001). Sulfite can induce structural and functional changes in the rats' cerebellum and concomitant curcumin prescription plays a neuroprotective role. PMID:24465141

Noorafshan, Ali; Rashidiani-Rashidabadi, Ali; Karbalay-Doust, Saied; Poostpasand, Aghdas; Abdollahifar, Mohammad-Amin; Asadi-Golshan, Reza

2013-12-01

348

Protein Radical Formation Resulting from Eosinophil Peroxidase-catalyzed Oxidation of Sulfite*  

PubMed Central

Eosinophil peroxidase (EPO) is an abundant heme protein in eosinophils that catalyzes the formation of cytotoxic oxidants implicated in asthma, allergic inflammatory disorders, and cancer. It is known that some proteins with peroxidase activity (horseradish peroxidase and prostaglandin hydroperoxidase) can catalyze oxidation of bisulfite (hydrated sulfur dioxide), leading to the formation of sulfur trioxide anion radical (·SO3?). This free radical further reacts with oxygen to form peroxymonosulfate anion radical (?O3SOO·) and the very reactive sulfate anion radical (SO4??), which is nearly as strong an oxidant as the hydroxyl radical. However, the ability of EPO to generate reactive sulfur radicals has not yet been reported. Here we demonstrate that eosinophil peroxidase/H2O2 is able to oxidize bisulfite, ultimately forming the sulfate anion radical (SO4??), and that these reactive intermediates can oxidize target proteins to protein radicals, thereby initiating protein oxidation. We used immuno-spin trapping and confocal microscopy to study protein oxidation by EPO/H2O2 in the presence of bisulfite in a pure enzymatic system and in human promyelocytic leukemia HL-60 clone 15 cells, maturated to eosinophils. Polyclonal antiserum raised against the spin trap 5,5-dimethyl-1-pyrroline N-oxide (DMPO) detected the presence of DMPO covalently attached to the proteins resulting from the DMPO trapping of protein free radicals. We found that sulfite oxidation mediated by EPO/H2O2 induced the formation of radical-derived DMPO spin-trapped human serum albumin and, to a lesser extent, of DMPO-EPO. These studies suggest that EPO-dependent oxidative damage may play a role in tissue injury in bisulfite-exacerbated eosinophilic inflammatory disorders. PMID:20501663

Ranguelova, Kalina; Chatterjee, Saurabh; Ehrenshaft, Marilyn; Ramirez, Dario C.; Summers, Fiona A.; Kadiiska, Maria B.; Mason, Ronald P.

2010-01-01

349

White button, portabella, and shiitake mushroom supplementation up-regulates interleukin-23 secretion in acute dextran sodium sulfate colitis C57BL/6 mice and murine macrophage J.744.1 cell line.  

PubMed

Interleukin-23 (IL-23), a cytokine produced primarily by dendritic cells, is involved in host defense against gut pathogens and promotes innate immunity and inflammatory responses through the IL-23/interleukin-17 axis. We previously reported that extracts from edible mushrooms enhanced antimicrobial ?-defensin production n HL60 cells. Because IL-23 is involved in defensin production, we hypothesized that edible mushrooms may modulate its secretion and gut inflammation. Eight-week-old C57BL/6 mice were fed the AIN76 diet or the same diet supplemented with 5% white button (WBM), portabella, or shiitake mushrooms. To assess in vivo and in vitro cytokine secretion, 7 to 8 mice per group received 3% dextran sodium sulfate (DSS) in drinking water during the last 5 days of the 6-week feeding period. To delineate the mechanisms by which mushrooms alter IL-23 secretion, J.744.1 cells were incubated with (100 ?g/mL) WBM, portabella, and shiitake extracts without and with 100 ?g/mL curdlan (a dectin-1 agonist) or 1 mg/mL laminarin (a dectin-1 antagonist). The dectin-1 receptor is a pattern-recognition receptor found in phagocytes, and its activation promotes antimicrobial innate immunity and inflammatory responses. In DSS-untreated mice, mushrooms significantly increased IL-23 plasma levels but decreased those of interleukin-6 (IL-6) (P < .05). In DSS-treated mice, mushroom-supplemented diets increased IL-6 and IL-23 levels (P < .05). Mushroom extracts potentiated curdlan-induced IL-23 secretion, and mushroom-induced IL-23 secretion was not blocked by laminarin in vitro, suggesting the involvement of both dectin-1-dependent and dectin-1-independent pathways. Although all mushrooms tended to increase IL-6 in the colon, only WBM and shiitake tended to increase IL-23 levels. These data suggest that edible mushrooms may enhance gut immunity through IL-23. PMID:23684440

Chandra, Lawrance C; Traoré, Djibril; French, Christine; Marlow, Denver; D'Offay, Jean; Clarke, Stephen L; Smith, Brenda J; Kuvibidila, Solo

2013-05-01

350

Upregulation of KCa3.1 K(+) channel in mesenteric lymph node CD4(+) T lymphocytes from a mouse model of dextran sodium sulfate-induced inflammatory bowel disease.  

PubMed

The intermediate-conductance Ca(2+)-activated K(+) channel KCa3.1/KCNN4 plays an important role in the modulation of Ca(2+) signaling through the control of the membrane potential in T lymphocytes. Here, we study the involvement of KCa3.1 in the enlargement of the mesenteric lymph nodes (MLNs) in a mouse model of inflammatory bowel disease (IBD). The mouse model of IBD was prepared by exposing male C57BL/6J mice to 5% dextran sulfate sodium for 7 days. Inflammation-induced changes in KCa3.1 activity and the expressions of KCa3.1 and its regulators in MLN CD4(+) T lymphocytes were monitored by real-time PCR, Western blot, voltage-sensitive dye imaging, patch-clamp, and flow cytometric analyses. Concomitant with an upregulation of KCa3.1a and nucleoside diphosphate kinase B (NDPK-B), a positive KCa3.1 regulator, an increase in KCa3.1 activity was observed in MLN CD4(+) T lymphocytes in the IBD model. Pharmacological blockade of KCa3.1 elicited the following results: 1) a significant decrease in IBD disease severity, as assessed by diarrhea, visible fecal blood, inflammation, and crypt damage of the colon and MLN enlargement compared with control mice, and 2) the restoration of the expression levels of KCa3.1a, NDPK-B, and Th1 cytokines in IBD model MLN CD4(+) T lymphocytes. These findings suggest that the increase in KCa3.1 activity induced by the upregulation of KCa3.1a and NDPK-B may be involved in the pathogenesis of IBD by mediating the enhancement of the proliferative response in MLN CD4(+) T lymphocyte and, therefore, that the pharmacological blockade of KCa3.1 may decrease the risk of IBD. PMID:24674776

Ohya, Susumu; Fukuyo, Yuka; Kito, Hiroaki; Shibaoka, Rina; Matsui, Miki; Niguma, Hiroki; Maeda, Yasuhiro; Yamamura, Hisao; Fujii, Masanori; Kimura, Kazunori; Imaizumi, Yuji

2014-05-15

351

Optimization of Sulfide/Sulfite Pretreatment of Lignocellulosic Biomass for Lactic Acid Production  

PubMed Central

Potential of sodium sulfide and sodium sulfite, in the presence of sodium hydroxide was investigated to pretreat the corncob (CC), bagasse (BG), water hyacinth and rice husk (RH) for maximum digestibility. Response Surface Methodology was employed for the optimization of pretreatment factors such as temperature, time and concentration of Na2S and Na2SO3, which had high coefficient of determination (R2) along with low probability value (P), indicating the reliable predictability of the model. At optimized conditions, Na2S and Na2SO3 remove up to 97% lignin, from WH and RH, along with removal of hemicellulose (up to 93%) during pretreatment providing maximum cellulose, while in BG and CC; 75.0% and 90.0% reduction in lignin and hemicellulose was observed. Saccharification efficiency of RH, WH, BG and CC after treatment with 1.0% Na2S at 130°C for 2.3–3.0 h was 79.40, 85.93, 87.70, and 88.43%, respectively. WH treated with Na2SO3 showed higher hydrolysis yield (86.34%) as compared to Na2S while other biomass substrates showed 2.0–3.0% less yield with Na2SO3. Resulting sugars were evaluated as substrate for lactic acid production, yielding 26.48, 25.36, 31.73, and 30.31 gL?1 of lactic acid with 76.0, 76.0, 86.0, and 83.0% conversion yield from CC, BG, WH, and RH hydrolyzate, respectively. PMID:24058918

Adnan, Ahmad; Qureshi, Fahim Ashraf

2013-01-01

352

Optimization of sulfide/sulfite pretreatment of lignocellulosic biomass for lactic acid production.  

PubMed

Potential of sodium sulfide and sodium sulfite, in the presence of sodium hydroxide was investigated to pretreat the corncob (CC), bagasse (BG), water hyacinth and rice husk (RH) for maximum digestibility. Response Surface Methodology was employed for the optimization of pretreatment factors such as temperature, time and concentration of Na?S and Na?SO?, which had high coefficient of determination (R²) along with low probability value (P), indicating the reliable predictability of the model. At optimized conditions, Na?S and Na?SO? remove up to 97% lignin, from WH and RH, along with removal of hemicellulose (up to 93%) during pretreatment providing maximum cellulose, while in BG and CC; 75.0% and 90.0% reduction in lignin and hemicellulose was observed. Saccharification efficiency of RH, WH, BG and CC after treatment with 1.0% Na?S at 130°C for 2.3-3.0 h was 79.40, 85.93, 87.70, and 88.43%, respectively. WH treated with Na?SO? showed higher hydrolysis yield (86.34%) as compared to Na?S while other biomass substrates showed 2.0-3.0% less yield with Na?SO?. Resulting sugars were evaluated as substrate for lactic acid production, yielding 26.48, 25.36, 31.73, and 30.31 gL?¹ of lactic acid with 76.0, 76.0, 86.0, and 83.0% conversion yield from CC, BG, WH, and RH hydrolyzate, respectively. PMID:24058918

Idrees, Muhammad; Adnan, Ahmad; Qureshi, Fahim Ashraf

2013-01-01

353

Sulfur X-Ray Absorption And Vibrational Spectroscopic Study of Sulfur Dioxide, Sulfite, And Sulfonate Solutions And of the Substituted Sulfonate Ions X(3)CSO(3-)(X = H, Cl, F)  

Microsoft Academic Search

Sulfur K-edge X-ray absorption near-edge structure (XANES) spectra have been recorded and the S(1s) electron excitations evaluated by means of density functional theory-transition potential (DFT-TP) calculations to provide insight into the coordination, bonding, and electronic structure. The XANES spectra for the various species in sulfur dioxide and aqueous sodium sulfite solutions show considerable differences at different pH values in the

E. Damian Risberg; L. Eriksson; J. Mink; L. G. M. Pettersson; M. Yu. Skripkin; M. Sandstrom

2009-01-01

354

Spectrophotometric Determination of Total Sulfite in White Wine Samples Using Crude Extracts from Flowers  

NASA Astrophysics Data System (ADS)

A didactic spectrophotometric method for determining the sulfite content in white wine samples is proposed. It is based upon a discoloring reaction between flower anthocyanins and the sulfite in basic media. Students' results obtained from iodometric data agreed well with results obtained by the proposed procedure. The use of natural dyes attracted students' interest, enhancing the learning process.

Flora Barbosa Soares, Márlon Herbert; Ramos, Luiz Antonio; Tadeu Gomes Cavalheiro, Éder

2002-09-01

355

Uses and analysis of sulfites in the corn wet milling industry.  

PubMed

This paper reviews the purpose and principal uses of sulfiting agents in corn wet milling, together with the residual levels of sulfiting agents in finished products. Comparative results of the Monier-Williams method, an iodometric method, and a pararosaniline method for sulfur dioxide are discussed. PMID:3949708

Coker, L E

1986-01-01

356

Reply to "Mechanism of the Oscillatory Bromate Oxidation of Sulfite and Ferrocyanide in a  

E-print Network

Reply to "Mechanism of the Oscillatory Bromate Oxidation of Sulfite and Ferrocyanide in a CSTR of the bromite-sulfite-ferrocyanide (BSF) system is better described by a mechanism that includes the component reaction of bromate and sulfur(IV)2 than by the mechanism proposed by Edblom et al.3 (ELOKE), which focuses

Epstein, Irving R.

357

A real-time colorimetric and ratiometric fluorescent probe for sulfite.  

PubMed

A real-time colorimetric and ratiometric fluorescent probe based on modulating the intramolecular charge transfer (ICT) of the coumarin platform for selective detection of sulfite is presented. This reaction based probe utilized the Michael addition to the dicyano-vinyl group with the detection limit of 5.8 × 10(-5) M. The probe displayed a high selectivity for sulfite over other anions and reactive sulfur especially for biothiols including cysteine (Cys), homocysteine (Hcy) and glutathione (GSH), with about 100 nm blue shift and more than 230 times intensity ratios change of the emission spectrum. Meanwhile, it could be easily observed that the probe for sulfite changes from red to pale yellow by the naked eye, and from red to blue under UV lamp immediately after the sulfite is added. To the best of our knowledge, it is the fastest response probe for sulfite ever reported, which could give a colorimetric and ratiometric fluorescent response instantly. PMID:23563108

Wu, Ming-Yu; He, Ting; Li, Kun; Wu, Ming-Bo; Huang, Zheng; Yu, Xiao-Qi

2013-05-21

358

Effects of raised temperature of sulfate solutions on the sulfate resistance of mortars with and without silica fume  

SciTech Connect

Effect of raised temperature of sodium sulfate and magnesium sulfate solutions on the resistance of mortars was investigated. Experimental study was carried out on mortars with and without silica fume. Sulfate concentration was 18,000 mg/L as SO{sub 4}{sup 2{minus}} for the sodium sulfate and 13,000 mg/L magnesium sulfate solutions. Temperatures of solutions were 20 and 40 C. Some physical and mechanical properties were tested during the 300 days of sulfate exposure. Test results showed that raised solution temperature did not accelerate the deterioration of mortars under the conditions used in this research. Moreover, raised temperature improved many properties of the specimens. It can be suggested that there are some problems with raising the temperature of sulfate solution as an accelerated test method.

Akoez, F.; Koral, S.; Yuezer, N. [Yildiz Technical Univ., Istanbul (Turkey)] [Yildiz Technical Univ., Istanbul (Turkey); Tuerker, F. [Akdeniz Univ., Antalya (Turkey)] [Akdeniz Univ., Antalya (Turkey)

1999-04-01

359

Studies of Sulfate Utilization of Algae  

PubMed Central

Crude extracts of wild-type Euglena grown in the light (WTL) or in the dark (WTD) and a mutant lacking detectable plastid DNA (W3BUL) contain adenosine 5?-phosphosulfate (APS) sulfotransferase. Isotope dilution experiments indicate that adenosine 3?-phosphate 5?-phosphosulfate (PAPS) sulfotransferase is absent. Thiosulfonate reductase, requiring addition of NADH or NADPH but not ferredoxin, and O-acetyl-l-serine sulfhydrylase, the two other enzymes of the bound intermediate pathway of assimilatory sulfate reduction, are also present. Increasing levels of all three enzymes were found in WTL, WTD, and W3BUL during logarithmic growth but the various activities were similar at comparable stages of growth in all three types of cell. These results show that the three enzymes are not coded in the chloroplast DNA and are not restricted to Euglena cells having fully developed chloroplasts. Consistent with this, they do not increase during light-induced chloroplast development in resting cells and are found to be enriched in the mitochondrial fraction. Further resolution of this fraction on sucrose gradients shows that the APS sulfotransferase is associated with both the microbody (glyoxysomal) and mitochondrial fractions while the thiosulfonate reductase and O-acetyl-l-serine sulfhydrylase are associated only with the mitochondria. Thus the three known enzymes of the bound pathway of assimilatory sulfate reduction are present in Euglena mitochondria. Although the activity of the entire bound pathway (APS to cysteine) is low in extracts, addition of dithiothreitol which releases free sulfite from the product of the APS sulfotransferase reaction, causes an increase in reduction activity indicating that a sulfite reductase is also present. It remains to be shown which reducing system is the significant one in vivo in Euglena. PMID:16659497

Brunold, Christian; Schiff, Jerome A.

1976-01-01

360

Acid/Base Recovery From Sodium Sulfate  

E-print Network

1500 1000 500 HEAVY EXTENQED UTE CATALYST LOAOING pH.2. 65c 15 kAlM2 FIGURE 3 TIR-2000 COATING LIFE 150 GPL SULFURIC ACID 150 deg. C 100000 o:L1F:..:Ec..: T1 "'::::E",IDA::::V::::S,,-1---------, '0000 '000 100 ~ ID 0.' '0 '00 CURRENT... 1500 1000 500 HEAVY EXTENQED UTE CATALYST LOAOING pH.2. 65c 15 kAlM2 FIGURE 3 TIR-2000 COATING LIFE 150 GPL SULFURIC ACID 150 deg. C 100000 o:L1F:..:Ec..: T1 "'::::E",IDA::::V::::S,,-1---------, '0000 '000 100 ~ ID 0.' '0 '00 CURRENT...

Niksa, M. J.

361

Reaction of hydrogen sulfide with oxygen in the presence of sulfite  

SciTech Connect

Commonly, abatement of hydrogen sulfide emission from a geothermal powerplant requires that hydrogen sulfide dissolved in the cooling water be eliminated by chemical reaction. Oxidation by atmospheric oxygen is the preferred reaction, but requires a suitable catalyst. Nickel is the most potent and thereby cheapest catalyst for this purpose. One mg/L nickel in the cooling water would allow 99% removal of hydrogen sulfide to be attained. A major drawback of catalytic air oxidation is that colloidal sulfur is a major reaction product; this causes rapid sludge accumulation and deposition of sulfur scale. We studied the kinetics and product distribution of the reaction of hydrogen sulfide with oxygen, catalyzed by nickel. Adding sodium sulfite to the solution completely suppresses formation of colloidal sulfur by converting it to thiosulfate. The oxidation reaction is an autocatalytic, free radical chain reaction. A rate expression for this reaction and a detailed reaction mechanism were developed. Nickel catalyzes the chain initiation step, and polysulfidoradical ions propagate the chains. Several complexes of iron and cobalt were also studied. Iron citrate and iron N-hydroxyEDTA are the most effective iron based catalysts. Uncomplexed cobalt is as effective as nickel, but forms a precipitate of cobalt oxysulfide and is too expensive for practical use. 33 figures, 9 tables.

Weres, O.; Tsao, L.

1983-01-14

362

Theoretical study on the reactivity of sulfate species with hydrocarbons  

NASA Astrophysics Data System (ADS)

The abiotic, thermochemically controlled reduction of sulfate to hydrogen sulfide coupled with the oxidation of hydrocarbons, is termed thermochemical sulfate reduction (TSR), and is an important alteration process that affects petroleum accumulations in nature. Although TSR is commonly observed in high-temperature carbonate reservoirs, it has proven difficult to simulate in the laboratory under conditions resembling nature. The present study was designed to evaluate the relative reactivities of various sulfate species in order to provide greater insight into the mechanism of TSR and potentially to fill the gap between laboratory experimental data and geological observations. Accordingly, quantum mechanics density functional theory (DFT) was used to determine the activation energy required to reach a potential transition state for various aqueous systems involving simple hydrocarbons and different sulfate species. The entire reaction process that results in the reduction of sulfate to sulfide is far too complex to be modeled entirely; therefore, we examined what is believed to be the rate limiting step, namely, the reduction of sulfate S(VI) to sulfite S(IV). The results of the study show that water-solvated sulfate anions SO42- are very stable due to their symmetrical molecular structure and spherical electronic distributions. Consequently, in the absence of catalysis, the reactivity of SO42- is expected to be extremely low. However, both the protonation of sulfate to form bisulfate anions ( HSO4-) and the formation of metal-sulfate contact ion-pairs could effectively destabilize the sulfate molecular structure, thereby making it more reactive. Previous reports of experimental simulations of TSR generally have involved the use of acidic solutions that contain elevated concentrations of HSO4- relative to SO42-. However, in formation waters typically encountered in petroleum reservoirs, the concentration of HSO4- is likely to be significantly lower than the levels used in the laboratory, with most of the dissolved sulfate occurring as SO42-, aqueous calcium sulfate ([CaSO 4] (aq)), and aqueous magnesium sulfate ([MgSO 4] (aq)). Our calculations indicate that TSR reactions that occur in natural environments are most likely to involve bisulfate ions ( HSO4-) and/or magnesium sulfate contact ion-pairs ([MgSO 4] CIP) rather than 'free' sulfate ions ( SO42-) or solvated sulfate ion-pairs, and that water chemistry likely plays a significant role in controlling the rate of TSR.

Ma, Qisheng; Ellis, Geoffrey S.; Amrani, Alon; Zhang, Tongwei; Tang, Yongchun

2008-09-01

363

Process for removing nitrogen oxides from gaseous mixtures  

Microsoft Academic Search

Gaseous mixtures containing nitrogen oxides are contacted with an aqueous solution containing sodium sulfite, trisodium imidobissulfate and sodium sulfate while adjusting the pH thereof by sodium hydroxide or sodium carbonate, and sulfur dioxide is contacted therewith simultaneously or thereafter to produce disodium imidobissulfate and sodium hydrogensulfate. Sodium hydroxide is then added to deposit sodium sulfate 10 hydrate firstly and trisodium

Y. Ito; Y. Yasumoto; E. Masuda; H. Suzuki

1978-01-01

364

Salicylate-induced depletion of endogenous inorganic sulfate. Potential role in the suppression of sulfated glycosaminoglycan synthesis in murine articular cartilage.  

PubMed

Sodium salicylate has been shown to suppress glycosaminoglycan (GAG) synthesis by articular hyaline cartilage in vitro. We investigated the in vivo effect of sodium salicylate on murine patellar cartilage, using incorporation of intraperitoneally administered 35S-sulfate as a measure of sulfated GAG synthesis. Our results indicated that a single dose of sodium salicylate (200 mg/kg) inhibited in vivo sulfated GAG synthesis by 56%, compared with controls, and had no effect on sulfated GAG breakdown. A striking finding was that sodium sulfate treatment reduced the serum concentration of inorganic sulfate from 1.1 mM to approximately 0.3 mM, and that this serum reduction was associated with a twofold increase in urinary excretion of sulfate. Using anatomically intact patellar cartilage, in vitro studies clearly showed that, in concentrations reached in vivo (greater than or equal to 1 mM), salicylate suppressed murine chondrocyte GAG synthesis. However, in the presence of serum, the effects of 1 mM salicylate were abolished. We also found that sulfated GAG synthesis was clearly inhibited at low concentrations of sulfate (less than 0.5 mM). Our data indicate that sodium salicylate can suppress articular chondrocyte sulfated GAG synthesis in vivo, and that this effect may particularly be due to a drug-induced reduction of endogenous sulfate. PMID:4026888

de Vries, B J; van den Berg, W B; van de Putte, L B

1985-08-01

365

40 CFR 63.444 - Standards for the pulping system at sulfite processes.  

Code of Federal Regulations, 2010 CFR

...HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES National Emission Standards for Hazardous Air Pollutants from the Pulp and Paper Industry § 63.444 Standards for the pulping system at sulfite processes. (a) The owner or operator of...

2010-07-01

366

40 CFR 63.444 - Standards for the pulping system at sulfite processes.  

...HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES National Emission Standards for Hazardous Air Pollutants from the Pulp and Paper Industry § 63.444 Standards for the pulping system at sulfite processes. (a) The owner or operator of...

2014-07-01

367

40 CFR 63.444 - Standards for the pulping system at sulfite processes.  

Code of Federal Regulations, 2011 CFR

...HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES National Emission Standards for Hazardous Air Pollutants from the Pulp and Paper Industry § 63.444 Standards for the pulping system at sulfite processes. (a) The owner or operator of...

2011-07-01

368

40 CFR 63.444 - Standards for the pulping system at sulfite processes.  

Code of Federal Regulations, 2012 CFR

...HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES National Emission Standards for Hazardous Air Pollutants from the Pulp and Paper Industry § 63.444 Standards for the pulping system at sulfite processes. (a) The owner or operator of...

2012-07-01

369

40 CFR 63.444 - Standards for the pulping system at sulfite processes.  

Code of Federal Regulations, 2013 CFR

...HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES National Emission Standards for Hazardous Air Pollutants from the Pulp and Paper Industry § 63.444 Standards for the pulping system at sulfite processes. (a) The owner or operator of...

2013-07-01

370

Optimal Conditions for Masking of Sulfite Anions with Formaldehyde in Iodometric Titration of Photographic Fixing Solutions  

Microsoft Academic Search

The iodometric titration of photographic fixing solutions can be simplified by masking sulfite anions with 3% aqueous formaldehyde in a weakly acidic medium, instead of their standard masking with concentrated aqueous formaldehyde in weakly alkaline solutions.

V. N. Kiryushov; L. I. Skvortsova

2005-01-01

371

Use of Sulfite and Hydrogen Peroxide To Control Bacterial Contamination in Ethanol Fermentation  

Microsoft Academic Search

the same concentrations did not change the viability of theSaccharomyces cerevisiaestrain used in this process. Sulfite was effective only in the presence of oxygen. Bacteria showed differences in their susceptibilities to sulfite. Facultatively heterofermentative Lactobacillus casei 4-3 was more susceptible than was obligatory heterofermentative Lactobacillus fermentum 7-1. The former showed higher enzyme activities involved in the production and consumption of

IN SEOP CHANG; BYUNG HONG KIM; ANDPYONG KYUN SHIN

1997-01-01

372

Capillary electrophoretic determination of sulfite using the zone-passing technique of in-capillary derivatization  

Microsoft Academic Search

A new capillary electrophoretic (CE) method was developed for the simple and selective determination of sulfite. The proposed method is based on the in-capillary derivatization of sulfite with iodine using the zone-passing technique and direct UV detection of iodide formed. The optimal conditions for the separation and derivatization reaction were established by varying concentration of iodine, electrolyte pH and applied

Giedre Jankovskiene; Zydrunas Daunoravicius; Audrius Padarauskas

2001-01-01

373

Sulfite increases lipoperoxidation and decreases the activity of catalase in brain of rats  

Microsoft Academic Search

The main objective of this study was to investigate the in vitro effects of sulfite, a metabolite accumulated in isolated\\u000a sulfite oxidase deficiency, on Na +, K +-ATPase activity and on some parameters of oxidative stress, namely thiobarbituric acid-reactive substances (TBARS) and catalase\\u000a activity (antioxidant enzyme) in cerebral cortex, striatum and hippocampus from 10- and 60-day-old rats. Results showed that

Fábria Chiarani; Caren S. Bavaresco; Carlos S. Dutra-Filho; Carlos Alexandre Netto; Angela T. S. Wyse

2008-01-01

374

A rapid method for the determination of sulfur dioxide in sulfited pre-peeled potatoes  

Microsoft Academic Search

Summary  A simple method has been developed for determining the sulfur dioxide content of sulfited, fresh potatoes. A 100 gram sample\\u000a of potato is homogenized in a buffer solution at pH 4.4, which was found to reduce the oxidation of the sulfite to a negligible\\u000a amount during the extraction and subsequent filtration. An aliquot of the filtered extract is then titrated

L. R. Ross; R. H. Treadway

1960-01-01

375

Oxygen isotope biogeochemistry of pore water sulfate in the deep biosphere: Dominance of isotope exchange reactions with  

E-print Network

of dissolved and solid sulfur species in marine sed- iments. Experiments and field data show that the d18 OSO4 or by the oxidation of sulfite to sulfate. Here we report d18 OSO4 2Ã? values from interstitial water samples of ODP to explain our d18 OSO4 2Ã? data, and that the data are well explained by a model using oxygen isotope

Gilli, Adrian

376

Desulfovirga adipica gen. nov., sp. nov., an adipate-degrading, Gram-negative, sulfate-reducing bacterium  

Microsoft Academic Search

A novel, mesophilic, Gram-negative bacterium was isolated from an anaerobic digestor for municipal wastewater. The bacterium degraded adipate in the presence of sulfate, sulfite, thiosulfate and elemental sulfur. (E)-2- Hexenedioate accumulated transiently in the degradation of adipate. (E)-2- Hexenedioate, (E)-3-hexenedioate, pyruvate, lactate, C1-C12 straight-chain fatty acids and C2-C10 straight-chain primary alcohols were also utilized as electron donors. 3-Phenylpropionate was oxidized

Kazuhiro Tanaka; Erko Stackebrandt; Shigehiro Tohyama; Tadashi Eguchi

377

Effects of low concentrations of bisulfite-sulfite and nitrite on microorganisms.  

PubMed Central

A wide range of microorganisms was tested to determine their sensitivity to low concentrations of bisulfite-sulfite and nitrite, solubility products of SO2 and NO2, respectively. Photosynthesis by blue-green algae (cyanobacteria) was more strongly inhibited by 0.1 mM bisulfite-sulfite and 1 mM nitrite at pH 6.0 than photosynthesis by eucaryotic algae and respiration of bacteria, fungi, and protozoa. At pH 7.7, blue-green algae were still more sensitive to bisulfite-sulfite and nitrite than eucaryotic algae, but the toxicity of bisulfite-sulfite and nitrite decreased as the pH increased. Photosynthesis by Anabaena flos-aquae at pH 6.0 was inhibited 25% by a bisulfite-sulfite concentration of 10 micrometer and 15% by a nitrite concentration of 50 micrometer. Photosynthesis by the blue-green alga, Lyngbya sp., was not exceptionally sensitive to chlorate and thiosulfate. Acetylene-reducing activity of Beijerinckia indica was completely inhibited by 0.1 mM bisulfite-sulfite at pH 4.0, the suppression being decreased with increasing pH. PMID:646357

Wodzinski, R S; Labeda, D P; Alexander, M

1978-01-01

378

Sulfate Reducing Rate of SRB with Acetic, Propionic, n-Butyric Acids as Carbon Sources  

Microsoft Academic Search

The aim of this work was to determine the kind of short-chain volatile fatty acid, which is apt to be used by sulfate reducing bacteria (SRB). SRB was feed with culture media used sodium lactate as carbon source. Sulfate reducing rate and different short-chain volatile fatty acids (VFA) utilization rate with SRB were studied. Sulfate variation curves were drawn and

Xiulan Song; Zhimin Zhang

2011-01-01

379

Electrochemiluminescence of terbium (III)-two fluoroquinolones-sodium sulfite system in aqueous solution  

NASA Astrophysics Data System (ADS)

The electrochemiluminescence (ECL) of Tb 3+-enoxacin-Na 2SO 3 system (ENX system) and Tb 3+-ofloxacin-Na 2SO 3 system (OFLX system) in aqueous solution is reported. ECL is generated by the oxidation of Na 2SO 3, which is enhanced by Tb 3+-fluoroquinolone (FQ) complex. The ECL intensity peak versus potential corresponds to oxidation of Na 2SO 3, and the ECL emission spectra (the peaks are at 490, 545, 585 and 620 nm) match the characteristic emission spectrum of Tb 3+, indicating that the emission is from the excited state of Tb 3+. The mechanism of ECL is proposed and the difference of ECL intensity between ENX system and OFLX system is explained. Conditions for ECL emission were optimized. The linear range of ECL intensity versus concentrations of pharmaceuticals is 2.0 × 10 -10-8.0 × 10 -7 mol l -1 for ENX and 6.0 × 10 -10-6.0 × 10 -7 mol l -1 for OFLX, respectively. A theoretical limit of detection is 5.4 × 10 -11 mol l -1 for ENX and 1.6 × 10 -10 mol l -1 for OFLX, respectively. The ECL was satisfactorily applied to the determination of the two FQs in dosage form and urine sample.

Chen, Shi-lv; Ding, Fen; Liu, Yu; Zhao, Hui-chun

2006-05-01

380

Batch slurry photocatalytic reactors for the generation of hydrogen from sulfide and sulfite waste streams under solar irradiation  

SciTech Connect

In this study, two solar slurry photocatalytic reactors i.e., batch reactor (BR) and batch recycle reactor with continuous supply of inert gas (BRRwCG) were developed for comparing their performance. The performance of the photocatalytic reactors were evaluated based on the generation of hydrogen (H{sub 2}) from water containing sodium sulfide (Na{sub 2}S) and sodium sulfite (Na{sub 2}SO{sub 3}) ions. The photoreactor of capacity 300 mL was developed with UV-vis transparent walls. The catalytic powders ((CdS/ZnS)/Ag{sub 2}S + (RuO{sub 2}/TiO{sub 2})) were kept suspended by means of magnetic stirrer in the BR and gas bubbling and recycling of the suspension in the BRRwCG. The rate constant was found to be 120.86 (einstein{sup -1}) for the BRRwCG whereas, for the BR it was found to be only 10.92 (einstein{sup -1}). The higher rate constant was due to the fast desorption of products and suppression of e{sup -}/h{sup +} recombination. (author)

Priya, R.; Kanmani, S. [Centre for Environmental Studies, Anna University, Chennai (India)

2009-10-15

381

Sulfation of tyrosine residues in coagulation factor V  

SciTech Connect

Sulfation of human coagulation factor V was investigated by biosynthetically labeling the products of HepG2 cells with ({sup 35}S)sulfate. There was abundant incorporation of the sulfate label into a product identified as factor V by immunoprecipitation, lability to proteases, affinity for the lectin jacalin, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Two or more sites in factor V incorporated sulfate as indicated by labeling of different peptide chains of factor Va. The 150-Kd activation fragment of factor Va incorporated the greatest amounts of sulfate. This fragment of factor Va was bound selectively by jacalin-agarose, reflecting its content of O-linked oligosaccharides. Analysis of an alkaline hydrolysate of sulfate-labeled factor Va by anion-exchange chromatography showed that the sulfate occurred partly in tyrosine sulfate residues and partly in alkaline-labile linkages. Sulfate groups are potentially important structural and functional elements in factor V, and labeling with (35S)sulfate provides a useful approach for examining the biosynthesis and processing of this protein. The hypothesis is advanced that sites of sulfation in factor V and several other plasma proteins contribute to the affinity and specificity of thrombin for these molecules, just as it does for the interaction of thrombin with the potent inhibitor hirudin from leeches.

Hortin, G.L. (Washington Univ. School of Medicine, St Louis, MO (USA))

1990-09-01

382

Effect of N,N-dimethyl acetamide on the critical micelle concentration of aqueous solutions of sodium surfactants  

Microsoft Academic Search

The variations of molar conductivity of various surfactants such as sodium caprylate, sodium laurate, sodium palmitate, sodium stearate, sodium oleate, sodium dodecyl sulfate, and lithium dodecyl sulfate with concentration of the surfactants for each of the solutions consisting of mixtures of varying concentrations of N,N-dimethyl acetamide in water at constant temperature of 22.0±0.2°C were studied. The critical micelle concentration (CMC)

Sadeq M. Alawi; M. Salim Akhter

2011-01-01

383

Sulfite disrupts brain mitochondrial energy homeostasis and induces mitochondrial permeability transition pore opening via thiol group modification.  

PubMed

Sulfite oxidase (SO) deficiency is biochemically characterized by the accumulation of sulfite, thiosulfate and S-sulfocysteine in tissues and biological fluids of the affected patients. The main clinical symptoms include severe neurological dysfunction and brain abnormalities, whose pathophysiology is still unknown. The present study investigated the in vitro effects of sulfite and thiosulfate on mitochondrial homeostasis in rat brain mitochondria. It was verified that sulfite per se, but not thiosulfate, decreased state 3, CCCP-stimulated state and respiratory control ratio in mitochondria respiring with glutamate plus malate. In line with this, we found that sulfite inhibited the activities of glutamate and malate (MDH) dehydrogenases. In addition, sulfite decreased the activity of a commercial solution of MDH, that was prevented by antioxidants and dithiothreitol. Sulfite also induced mitochondrial swelling and reduced mitochondrial membrane potential, Ca(2+) retention capacity, NAD(P)H pool and cytochrome c immunocontent when Ca(2+) was present in the medium. These alterations were prevented by ruthenium red, cyclosporine A (CsA) and ADP, supporting the involvement of mitochondrial permeability transition (MPT) in these effects. We further observed that N-ethylmaleimide prevented the sulfite-elicited swelling and that sulfite decreased free thiol group content in brain mitochondria. These findings indicate that sulfite acts directly on MPT pore containing thiol groups. Finally, we verified that sulfite reduced cell viability in cerebral cortex slices and that this effect was prevented by CsA. Therefore, it may be presumed that disturbance of mitochondrial energy homeostasis and MPT induced by sulfite could be involved in the neuronal damage characteristic of SO deficiency. PMID:24793416

Grings, Mateus; Moura, Alana P; Amaral, Alexandre U; Parmeggiani, Belisa; Gasparotto, Juciano; Moreira, José C F; Gelain, Daniel P; Wyse, Angela T S; Wajner, Moacir; Leipnitz, Guilhian

2014-09-01

384

Strength deterioration of high strength concrete in sulfate environment  

SciTech Connect

Sulfate in soil and groundwater may cause damage to the concrete in underground structures. In this paper, laboratory tests were performed to assess the damage of chemical attack by magnesium sulfate and sodium sulfate on normal and high strength concretes. The selected solutions were pure water and 10% sulfate solutions (sodium and magnesium), which were determined by consideration of the soil environment in Korea. The parameters in experimental programs were water-binder ratio, silica fume content, and the compressive strength of concrete. Observed differences in the characteristics between normal and high strength concretes are discussed, and a scheme for maximizing the resistance of high strength concrete against various kinds of sulfates is suggested.

Park, Y.S.; Suh, J.K.; Lee, J.H.; Shin, Y.S.

1999-09-01

385

Expression, purification and characterization of the sulfite reductase hemo-subunit, SiR-HP, from Acidithiobacillus ferrooxidans  

Microsoft Academic Search

Sulfite reductase (SiR) is a large and soluble enzyme which catalyzes the transfer of six electrons from NADPH to sulfite\\u000a to produce sulfide. The sulfite reductase flavoprotein (SiR-FP) contains both FAD and FMN, and the sulfite reductase hemoprotein\\u000a (SiR-HP) contains an iron–sulfur cluster coupled to a siroheme. The enzyme is arranged so that the redox cofactors in the\\u000a FAD-FMN-Fe4S4?Heme sequence

Jia Zeng; Ming Wang; Xiaojian Zhang; Yiping Wang; Chenbin Ai; Jianshe Liu; Guanzhou Qiu

2008-01-01

386

Sulfate resistance of high calcium fly ash concrete  

NASA Astrophysics Data System (ADS)

Sulfate attack is one of the mechanisms which can cause deterioration of concrete. In general, Class C fly ash mixtures are reported to provide poor sulfate resistance. Fly ashes, mainly those belonging to the Class C, were tested as per the ASTM C 1012 procedure to evaluate chemical sulfate resistance. Overall the Class C fly ashes showed poor resistance in the sulfate environment. Different strategies were used in this research work to improve the sulfate resistance of Class C fly ash mixes. The study revealed that some of the strategies such as use of low W/CM (water to cementing materials by mass ratio), silica fume or ultra fine fly ash, high volumes of fly ash and, ternary or quaternary mixes with suitable supplementary cementing materials, can successfully improve the sulfate resistance of the Class C fly ash mixes. Combined sulfate attack, involving physical and chemical action, was studied using sodium sulfate and calcium sulfate solutions. The specimens were subjected to wetting-drying cycles and temperature changes. These conditions were found to accelerate the rate of degradation of concrete placed in a sodium sulfate environment. W/CM was found to be the main governing factor in providing sulfate resistance to mixes. Calcium sulfate did not reveal damage as a result of mainly physical action. Characterization of the selected fly ashes was undertaken by using SEM, XRD and the Rietveld analysis techniques, to determine the relation between the composition of fly ashes and resistance to sulfate attack. The chemical composition of glass represented on the ternary diagram was the main factor which had a significant influence on the sulfate resistance of fly ash mixtures. Mixes prepared with fly ashes containing significant amounts of vulnerable crystalline phases offered poor sulfate resistance. Comparatively, fly ash mixes containing inert crystalline phases such as quartz, mullite and hematite offered good sulfate resistance. The analysis of hydrated lime-fly ash pastes confirmed that fly ash mortar or concrete mixes forming more monosulfate than ettringite before exposure to sulfates would offer poor sulfate resistance and vice versa. During quantitative Rietveld analysis carried out for determining ettringite, monosulfate and gypsum formed in the fly ash pastes, it was observed that fly ash mixtures showing more ettringite after exposures to sulfates, give poor sulfate resistance. A good relationship between the amounts of ettringite formed and expansions of mortar specimens in the ASTM C 1012 test was found.

Dhole, Rajaram

387

Crystallization of Chicken Egg White Lysozyme from Sulfate Salts  

NASA Technical Reports Server (NTRS)

It has been "known" that chicken egg white lysozyme does not crystallize from sulfate, particularly ammonium sulfate, salts, but instead gives amorphous precipitates. This has been the basis of several studies using lysozyme comparing macromolecule crystal nucleation and amorphous precipitation. Recently Ries-Kautt et al (Acta Cryst D50, (1994) 366) have shown that purified isoionic CEWL could be crystallized from low concentrations of sulfate at basic pH, and we subsequently showed that in fact CEWL could be purified in both the tetragonal and orthorhombic forms using ammonium sulfate over the pH range 4.0 to 7.8 (Acta Cryst D53, (1997) 795). We have now extended these observations to include a range of common sulfate salts, specifically sodium, potassium, rubidium, magnesium, and manganese sulfates. In all cases but the manganese sulfates both the familiar tetragonal and orthorhombic forms were obtained, with unit cell dimensions close to those known for the "classic" sodium chloride crystallized forms. Manganese sulfate has only yielded orthorhombic crystals to date. All crystallizations were carried out using low (typically less than or equal to 6 M) salt and high (greater than approximately 90 mg/ml) protein concentrations. As with ammonium sulfate, the tetragonal - orthorhombic phase shift appears to be a function of both the temperature and the protein concentration, with higher temperatures and concentrations favoring the orthorhombic and lower the tetragonal form. The phase change range is somewhat reduced for the sulfate salts, depending upon conditions being typically between approximately 15 - 20 C. Both the magnesium and manganese sulfates gave crystals at salt concentrations over 0.6 M as well, with magnesium sulfate giving a very slowly nucleating and growing hexagonal form. A triclinic crystal form, characterized by aggressively small crystals (typically 0.1 mm in size) has been occasionally obtained from ammonium sulfate. Finally, preliminary spot solubility determinations have suggested that in some cases the solubility increases with increasing salt concentrations.

Forsythe, Elizabeth; Pusey, Marc

1998-01-01

388

Stability of milrinone and epinephrine, atropine sulfate, lidocaine hydrochloride, or morphine sulfate injection.  

PubMed

The stability of both drug components of admixtures of milrinone and epinephrine, atropine sulfate, lidocaine hydrochloride, morphine sulfate, calcium chloride, or sodium bicarbonate injections was studied. Duplicate solutions of admixtures of milrinone injection 1 mg/mL and epinephrine injection 1:10,000, atropine sulfate injection 1 mg/mL, lidocaine hydrochloride injection 1%, morphine sulfate injection 8 mg/mL, calcium chloride injection 10%, or sodium bicarbonate injection 7.5% were prepared and stored in glass containers at 22-23 degrees C under fluorescent light. Samples were taken immediately and after 20 minutes for assay by high-performance liquid chromatography (HPLC). Milrinone at initial concentrations of 0.10-0.73 mg/mL showed no degradation in any of the solutions during the study period, nor was any degradation observed for lidocaine, morphine, atropine, or epinephrine. Milrinone 0.10-0.73 mg/mL is compatible with atropine sulfate, lidocaine hydrochloride, epinephrine, calcium chloride, or sodium bicarbonate in glass containers stored for 20 minutes at room temperature. These results support the use of milrinone in combination with these agents immediately after the preparation of admixtures. PMID:2278262

Wilson, T D; Forde, M D

1990-11-01

389

Sulfur X-ray absorption and vibrational spectroscopic study of sulfur dioxide, sulfite, and sulfonate solutions and of the substituted sulfonate ions X3CSO3- (X = H, Cl, F).  

PubMed

Sulfur K-edge X-ray absorption near-edge structure (XANES) spectra have been recorded and the S(1s) electron excitations evaluated by means of density functional theory-transition potential (DFT-TP) calculations to provide insight into the coordination, bonding, and electronic structure. The XANES spectra for the various species in sulfur dioxide and aqueous sodium sulfite solutions show considerable differences at different pH values in the environmentally important sulfite(IV) system. In strongly acidic (pH < approximately 1) aqueous sulfite solution the XANES spectra confirm that the hydrated sulfur dioxide molecule, SO2(aq), dominates. The theoretical spectra are consistent with an OSO angle of approximately 119 degrees in gas phase and acetonitrile solution, while in aqueous solution hydrogen bonding reduces the angle to approximately 116 degrees . The hydration affects the XANES spectra also for the sulfite ion, SO32-. At intermediate pH ( approximately 4) the two coordination isomers, the sulfonate (HSO3-) and hydrogen sulfite (SO3H-) ions with the hydrogen atom coordinated to sulfur and oxygen, respectively, could be distinguished with the ratio HSO3-:SO3H- about 0.28:0.72 at 298 K. The relative amount of HSO3- increased with increasing temperature in the investigated range from 275 to 343 K. XANES spectra of sulfonate, methanesulfonate, trichloromethanesulfonate, and trifluoromethanesulfonate compounds, all with closely similar S-O bond distances in tetrahedral configuration around the sulfur atom, were interpreted by DFT-TP computations. The energy of their main electronic transition from the sulfur K-shell is about 2478 eV. The additional absorption features are similar when a hydrogen atom or an electron-donating methyl group is bonded to the -SO3 group. Significant changes occur for the electronegative trichloromethyl (Cl3C-) and trifluoromethyl (F3C-) groups, which strongly affect the distribution especially of the pi electrons around the sulfur atom. The S-D bond distance 1.38(2) A was obtained for the deuterated sulfonate (DSO3-) ion by Rietveld analysis of neutron powder diffraction data of CsDSO3. Raman and infrared absorption spectra of the CsHSO3, CsDSO3, H3CSO3Na, and Cl3CSO3Na.H2O compounds and Raman spectra of the sulfite solutions have been interpreted by normal coordinate calculations. The C-S stretching force constant for the trichloromethanesulfonate ion obtains an anomalously low value due to steric repulsion between the Cl3C- and -SO3 groups. The S-O stretching force constants were correlated with corresponding S-O bond distances for several oxosulfur species. PMID:17784748

Risberg, Emiliana Damian; Eriksson, Lars; Mink, János; Pettersson, Lars G M; Skripkin, Mikhail Yu; Sandström, Magnus

2007-10-01

390

ORIGINAL ARTICLE Quantifying Expression of a Dissimilatory (bi)Sulfite  

E-print Network

harbor sediments [14, 15, 36], but estimating the in situ rate of anaerobic PAH degradation with [14 C]-labelled PAHs are oxidized to 14 CO2 and the rate of degradation of the bulk pool of PAHs [36]. Although- carbons (PAHs) are anaerobically oxidized with the reduction of sulfate in a diversity of contaminated

Lovley, Derek

391

Sulfite determination by a biosensor based on bay leaf tissue homogenate: very simple and economical method.  

PubMed

Of all the food additives for which the FDA has received adverse reaction reports, the ones that most closely resemble true allergens are sulfur-based preservatives. Sulfites are used primarily as antioxidants to prevent or reduce discoloration of light-colored fruits and vegetables, such as dried apples and potatoes, and to inhibit the growth of microorganisms in fermented foods such as wine. This work aims to prepare an electrochemical biosensor based on bay leaf tissue homogenate that contains polyphenol oxidase enzyme abundantly for sulfite detection in foods. The principle of the biosensor is based on the inhibition effect of sulfites on polyphenol oxidase in the bioactive layer. Optimum conditions for the biosensor, such as temperature and pH, were investigated. Some stability parameters of the biosensor were also identified. The biosensor showed a linear calibration graph in the range of 25-100 microM sulfite. The biosensor presents a very simple, economical, reliable, and feasible method for sulfite detection in foods. PMID:19418312

Teke, Mustafa; Sezgintürk, Mustafa Kemal; Dinçkaya, Erhan

2009-01-01

392

Sulfate in fetal development  

Microsoft Academic Search

Sulfate (SO42?) is an important nutrient for human growth and development, and is obtained from the diet and the intra-cellular metabolism of sulfur-containing amino acids, including methionine and cysteine. During pregnancy, fetal tissues have a limited capacity to produce sulfate, and rely on sulfate obtained from the maternal circulation. Sulfate enters and exits placental and fetal cells via transporters on

Paul A. Dawson

2011-01-01

393