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The Na-Cl cotransporter NCC is expressed in the distal convoluted tubule, activated by phosphorylation, and has been implicated in renal NaCl and [K.sup.+] homeostasis. The serum and glucocorticoid inducible kinase l (SGK1) contributes to renal NaCl retention and [K.sup.+] excretion, at least in part, by stimulating the epithelial [Na.sup.+] channel and [Na.sup.+]-[K.sup.+]-ATPase in the downstream segments of aldosterone-sensitive [Na.sup.+]/[K.sup.+] exchange. In this study we confirmed in wild-type mice (WT) that dietary NaCl restriction increases renal NCC expression and its phosphorylation at [Thr.sup.53], [Thr.sup.58], and [Ser.sup.71], respectively. This response, however, was attenuated in mice lacking SGK1 ([Sgk1.sup.-/-]), which may contribute to impaired NaCl retention in those mice. Total renal NCC expression and phosphorylation at [Thr.sup.53], [Thr.sup.58], and [Ser.sup.71] in WT were greater under low- compared with high-[K.sup.+] diet. This finding is consistent with a regulation of NCC to modulate [Na.sup.+] delivery to downstream segments of [Na.sup.+]/[K.sup.+] exchange, thereby modulating [K.sup.+] excretion. Dietary [K.sup.+]-dependent variation in renal expression of total NCC and phosphorylated NCC were not attenuated in [Sgk1.sup.-/-] mice. In fact, high-[K.sup.+] diet-induced NCC suppression was enhanced in [Sgk1.sup.-/-] mice. The hyperkalemia induced in [Sgk1.sup.-/-] mice by a high-[K.sup.+] diet may have augmented NCC suppression, thereby increasing [Na.sup.+] delivery and facilitating [K.sup.+] excretion in downstream segments of impaired [Na.sup.+]/[K.sup.+] exchange. In summary, changes in NaCl and [K.sup.+] intake altered NCC expression and phosphorylation, an observation consistent with a role of NCC in NaCl and [K.sup.+] homeostasis. The two maneuvers dissociated plasma aldosterone levels from NCC expression and phosphorylation, implicating additional regulators. Regulation of NCC expression and phosphorylation by dietary NaCl restriction appears to involve SGK1. with-no-lysine kinases; diuretic; epithelial sodium channel; intake; sodium chloride

Deuterium spin relaxation was used to examine the motion of enzyme-bound water on subtilisin Carlsberg colyophilized with inorganic salts for activation in different organic solvents. Spectral editing was used to ensure that the relaxation times were associated with relatively mobile deuterons, which were contributed almost entirely by [D.sub.2]O rather than hydrogen-deuteron exchange on the protein. The results indicate that the timescale of motion for residual water molecules on the biocatalyst, ([[tau].sub.c]) [D.sub.2]O, in hexane decreased from 65 ns (salt-free) to 0.58 ns (98% CsF) as [([k.sub.cat]/[K.sub.M]).sub.app] of the biocatalyst preparation increased from 0.092 [s.sup.-1]*[M.sup.-1] (saltfree) to 1,140 [s.sup.-1]*[M.sup.-1] (98% CsF). A similar effect was apparent in acetone; the timescale decreased from 24 ns (salt-free) to 2.87 ns (98% KF), with a corresponding increase in [([k.sub.cat]/ [K.sub.M]).sub.app] of 0.140 [s.sup.-1]*[M.sup.-1] (salt-free) to 12.8 [s.sup.-1]*[M.sup.-1] (98% KF). Although a global correlation between water mobility and enzyme activity was not evident, linear correlations between In[[([k.sub.cat]/[K.sub.M]).sub.app]] and ([[tau].sub.c])[D.sub.2]O were obtained for salt-activated enzyme preparations in both hexane and acetone. Furthermore, a direct correlation was evident between [([k.sub.cat]/[K.sub.M]).sub.app] and the total amount of mobile water per mass of enzyme. These results suggest that increases in enzymebound water mobility mediated by the presence of salt act as a molecular lubricant and enhance enzyme flexibility in a manner functionally similar to temperature. Greater flexibility may permit a larger degree of local transition-state mobility, reflected by a more positive entropy of activation, for the salt-activated enzyme compared with the salt-free enzyme. This increased mobility may contribute to the dramatic increases in biocatalyst activity. enzyme activation | organic solvents | salts | subtilisin Carlsberg

Mutnovskite, ideally [Pb.sub.2]As[S.sub.3](I,Cl,Br), is a new mineral from the high-temperature fumaroles of the Mutnovsky volcano, Kamchatka Peninsula, Russian Federation. It occurs as microscopic ruby-colored short-prismatic crystals up to 100 [micro]m across, closely associated with halogen-sulfosalts of Pb, Bi, and As, Cd-Pb-Bi sulfosalts, pyrite, anhydrite, and cristobalite. Mutnovskite is transparent in thin fragments with a dark-red to blue color. The crystals are soft and fragile. Cleavage and fracture were not observed and the Mohs hardness is approximately 2. In reflected light mutnovskite is silvery lead-grey in color with an iridescent tarnish. Pleochroism and anisotropy are not visible because of the strong orange internal reflections, especially in immersion. Reflectance percentages measured in air in the range 400-700 nm were tabulated. Reflectance percentages ([RM.sub.min], and [R.sub.max]) for the four COM wavelengths are 34.2, 34.6 (470 nm), 33.2, 33.5 (546 nm), 32.5, 32.7 (589 nm), and 31.4, 31.7 (650 nm), respectively. A mean of four electron microprobe analyses gave Pb 62.0(3), As 11.0(4), Bi 0.6(1), S 14.4(2), Se 0.2(3), I 8.9(3), CI 2.44(9), Br 1.1(7), Cu 0.03(2), Fe 0.01(1), total 100.7 wt%, corresponding, on the basis of a total of 7 atoms, to [Pb.sub.1.99][([As.sub.0.98][Bi.sub.0.02])).sub.[summation]1.00] [([S.sub.2.98][Se.sub.0.02]).sub.[summation]3.00][([I.sub.0.47][Cl.sub.0.46] [Br.sub.0.09]).sub.[summation1.02]. The nine strongest powder-diffraction lines [d in [Armstrong] (I/[I.sub.0])(hkl)] are: 4.69 (32) (002): 4.37 (67) (210): 3.34 (73) (020); 3.19 (100) (212); 2.715 (61) (022); 2.648 (66) (410); 2.539 (31) (213); 2.455 (29) (402); 1.894 (30) (232). Mutnovskite is orthorhombic, space group Pnma, with a = 11.543(1), b = 6.6764(7), and c = 9.359(1) [Armstrong], V = 721.3(1) [Armstrong], Z = 4. The crystal structure was solved and refined to R = 4.14%. It consists of three independent cation positions: Pb 1 and Pb2 have tricapped trigonal prismatic coordinations with S and I atoms (completed with one As atom in the case of Pb2), while As has threefold coordination with S atoms, which form the base of a trigonal pyramid with As at the apex. Pairs of Pb1-Pb2 prisms are connected in columns which extend along c. As[S.sub.3] coordinations are isolated from each other. S atoms and half of the Pb atoms form wavy close-packed layers. Two kinds of channels parallel to b occur between the layers. The smaller channels host As atoms close to the channel walls, with their lone-electron pairs occupying the median part, while the bigger ones accommodate rows of alternating halogen and Pb atoms. The new mineral is named after the type locality, the Mutnovsky volcano, Kamchatka Peninsula, Russian Federation. Keywords: Mutnovskite, chemical composition, new mineral, X-ray data, crystal struture, Kamchatka Peninsula, Mutnovsky volcano

The screening of the electrical potential at a charged solid surface in a molten salt is investigated in a computer simulation study. Despite pronounced oscillatory structure in the charge density, the structure and dynamics of the ions close to the interface are very similar to those in the bulk.

The effects of salts, KCl, NaCl, [K.sub.2]S[O.sub.4], [Na.sub.2]S[O.sub.4] and C[H.sub.3]COONa on the functional properties of benniseed (Sesamum radiatum) flour were studied. Results showed that the lowest gelation concentration of 18% observed in the absence of the salts was improved and found between 12 and 16% in the presence of different salts under consideration. The foaming capacity of about 18.0% in distilled water increased progressively from 30.5 [+ or -] 1.0 to 56.0 [+ or -] 0.6% depending on the concentrations and types of salts used. At low salts concentrations (0.5, 1.0 and 2.0%) the water absorption capacity decreased between 89.8 [+ or -] 0.5 and 85.0 [+ or -] 0.6% comparably with 182.0% in the absence of salts while the emulsion capacity also decreased between 43.5 [+ or -] 0.2 and 42.0 [+ or -] 0.9% with increase in salt concentrations of 0.5 to 10.0%. The foaming capacity and foaming stability that were 18.0 and 3.0% in the absence of the salts were improved and found within the range of 30.5 [+ or -] 1.0 to 56.0 [+ or -] 0.1% and 14.0 [+ or -] 0.8 to 22.4 [+ or -] 0.1% respectively. The dependence of protein solubility with pH was found to be a function of the type and concentration of salts considered. The curves showed that the solubility of the protein of the flour was found between the pH of 5.0 in the absence of the salt and varied between pH of 2.5 and 7.5 indicating that the protein is soluble in both the acidic and basic regions of pH scale. At high concentration of 5.0 and 10.0% of all the salts used, the solubility was high/enhanced at acidic region of pH, suggesting that the protein may be useful in acid food formulations.

The analysis of binding data of a ligand to a macromolecule in the presence of an additive can be classically formulated in terms of the linked functions of Wyman. In the case of a salt, this approach has been extended by Tanford such that the contributions of both salt and water are taken into account. In this paper, the extended Wyman theory was applied to high-performance affinity chromatography (HPAC) in order to define a general model describing the effects of the mobile-phase salts on the ligand binding. Various HPAC literature data, as well as our data concerning dansyl amino acid retention on a vancomycin stationary phase, were examined in relation to this model. From the results, this theoretical approach was considered to be adequate to describe accurately the salt dependence on solute retention. This work shows the importance of taking into account the effects of both ionic species and water in the investigation of relative contributions of the interactions involved in the ligand binding to immobilized receptor.

The synthesis, characterization and crystal structure of fluorantimonate salts of N5+ cations is described in terms of polynitrogen chemistry.

This study examines metal sulfides stability to oxidation in seawater. The acid volatile sulfide/simultaneously extracted metals (AVS/SEM) theory is used to evaluate sediment quality to predict the absence of toxicity of Ca, Cu, Ni, Pb, and Zn.

The synthesis, structures and reactivities of diselenocarboxylate and selenothiocarboxylate salts is described.

A new study examines the effect of different concentrations and types of salt on the thermal reversibility of hsian-tsao leaf gum/starch mixes.

This paper describes microelectrode voltammetry measurements of serf-diffusion coefficients and of heterogeneous Co(II/III) electron-transfer rate constants (k(super o)) in undiluted molten salts of three cobalt tris(bipyridine) perchlorate complexes in which the bipyridine ligands are 'tailed' with poly(propylene oxide) and poly(ethylene oxide) oligomers. The self-diffusion coefficients are measured with potential step chronoamperometry and range from 10(super-12) to 10(super -17) cm(super 2)/s, while the quasi-reversible reaction rate constants are measured using cyclic voltammetry and small potential steps and range from 10(super -7) to 10(super -12) cm/s. The k(super o) measurements are unusual in that when rate constants become smaller, the reaction remains quasi-reversible, because of concurrently decreasing self-diffusion rates. The measurements are, furthermore, accomplished in the face of uncompensated resistances that range from mega- to gigaohms, which is made possible by the combination of microelectrode properties and small diffusivities. The melt in which serf-diffusion and k(super o) values are smallest is at a temperature below its nominal glassing transition and in the regime of molecule-scale diffusion profiles.

Research has been conducted on the virus adsorption to microporous filters. The effect of mono-, di- and trivalent salts on this adsorption has been investigated.

Research has been conducted on the organocobalt(III) complexes. The use of EPR spectroscopy in understanding the photolysis mechanism of anaerobic solutions in aprotic solvents is described.

Research has been conducted on the ambient-temperature chloroaluminate molten salts. The use of these salts as solvents in isolating hexanuclear zirconium halide clusters from solid-state precursors is discussed.

Research has been conducted on the Cu(II)-containing ligand and Cu(II)-Ag(I) mixed-metal coordination polymers. The synthesis of these polymers is examined.

Research has been conducted on the one-to-one charge-transfer salt. The synthesis and single-crystal structure of this salt are described.

Research has been conducted on the lipoprotein(a) [Lp(a)]. The effect of NaCl and 6-aminohexanoic acid on the Lp(a) structure has been investigated.

Research has been conducted on the charge-transfer salts. The structural and magnetic properties of these salts have been investigated.

Research has been conducted on the new class of inorganic salts. The synthesis and properties of these salts are described.

Research has been conducted on the partially deuterated Tutton salt ammonium hexaaquacopper(II) sulfate. The EPR spectra variation measurements are presented.

Research has been conducted on the role of salt bridges in the stabilization of proteins. The NMR structure of a hyperthermophilic rubredoxin variant is described.

A novel mode of capillary electrochromatography (CEC), called dynamically modified strong cation-exchange CEC (DMSCX-CEC), is described in this paper. A column packed with a strong cation-exchange (SCX) packing material was dynamically modified with a long-chain quaternary ammonium salt, cetyltrimethylammonium bromide (CTAB), which was added to the mobile phase. CTAB ions were adsorbed onto the surface of the SCX packing material, and the resulting hydrophobic layer on this packing was used as the stationary phase. Using the dynamically modified SCX column, neutral solutes were separated with the CEC mode. The highest number of theoretical plates obtained was about 190 000/m, and the relative standard deviations (RSD's) for migration times and capacity factors of alkylbenzenes were less than 1.0% and 2.0% for five consecutive runs, respectively. The effects of CTAB and methanol concentrations and the pH value of the mobile phase on the electroosmotic flow and the separation mechanism were investigated. Excellent simultaneous separation of the basic and neutral solutes in DMSCX-CEC with a high-pH mobile phase was obtained. A mixture containing the acidic, basic, and neutral compounds was well separated in this mode with a low-pH mobile phase; however, peak tailing for basic compounds was observed in this mobile phase.

Research has been conducted on the generation of alpha-fluoromalonaldehyde sodium salt. The reaction of this salt with acid chlorides is described.

Research has been conducted on the electronic absorption and magnetic circular dichroism spectra for nitrate salts. Results indicate that low temperature enhances resolution.

Research has been conducted on the addition of enolate to pyridinium salt. Results demonstrate that acid-induced cyclization of 1,4-dihydropyridine produces tetracyclic 3,7-methano[1,4]diazonino[1,2-a]indole.

A study concerning the formation of uracil salts has been carried out. Examination of intramolecular interactions of cross-conjugated uracilylbetaines is discussed.

Research has been conducted on the addition of (super)n BuLi to solutions in producing dilithium diazasulfates. The use of solid-state (super)7 Li and (super)13 C NMR spectroscopy is discussed.

The authors focus on the development of the cheaper reagents for the large-scale peptide couplings. Experiments have demonstrated that 2-mercaptopyridine 1-oxide compound is an appropriate material for the preparation of uronium salts.

Research has been conducted on the tetranuclear copper(II) and nickel(II) complexes. A self-assembly process that involves a single ligand and metal salt is described.

The calculation of the dimerization energies of 2M (sub)2 (super)+ to give M (sub)4 (super)2+ has been carried out. The relative stabilities of these mono- and dication salts in the solid state are described.

A study of the onium transfer reaction of alkenyl(phenyl)iodonium tetrafluoroborates to prepare group 15 1-alkenyl(triphenyl)onium (P, As, Sb) tetrafluoroborates is presented. Results demonstrate that reaction involves base-induced reductive alpha-elimination of the iodonium salts.

A photopolymer for fabrication of volume-type transmission holograms, which are used primarily on the holographic reflector for reflective LCD's, is reported. This photopolymer consists of bisphenol-type epoxy resin and an acrylic monomer with diaryliodonium salt and 3-ketocoumarin as a complex initiator. The chemistry of the imaging formation is based on the radical polymerization of the monomer initiated by a holographic exposure, followed by the cationic polymerization of epoxy resin by UV exposure alder postexposure baking. The yellowish color of the hologram derivatives that resulted from the sensitizing dye and from the photospeed were improved to satisfy the specifications for the holographic reflector. The holographic reflector now gives brighter images.

Research has been conducted on an oxo-nitrosyl compound. The use of magnetic susceptibility measurements in characterizing the reaction of this compound with nickel(II) salts in methanol is described.

A study concerning the effects of the casein kinase 2 (CK-2) absence on cell processes is presented. Results demonstrate that CK-2 does not regulate sodium influx or efflux.

Research has been conducted on the Escherichia coli melibiose carrier. Results indicate an uncoupling of proton cotransport and reduction in N (super)+-coupled transport.

A study concerning the synthesis of complexes that involve lithium amidinates and lithium salts is presented. Experiments include crystallographic characterization of the complexes.

A new method of hydroxy double salts preparation is described. The reaction of ZnO with organic metal salts is analyzed.

The crystal and magnetic structures of the 1:1 salts of (M(dmit)2)- (M = Ni and Au) with the p-EPYNN (p-N-ethylpyridinium alpha-nitronyl nitroxide) cationic radical were investigated. Both crystal contain one-dimensional p-EPYNN chains with alternate head-to-tail orientation. However, a marked difference exists in the arrangement of these chains. The one-dimensional Au(dmit)2 chain is sandwiched between the p-EPYNN chains, resulting in isolation of each one-dimensional Au(dmit)2 chain. In contrast, every two chains of Ni(dmit)2 are sandwiched between the p-EPYNN chains, resulting in the Ni(dmit)2 ladder-chain formation.

Research has been conducted on the addition of Grignard reagents to quinolinium salts. Results indicate that this addition occurs at the 2- and 4-positions.

A study concerning the synthesis of bismuthonium salts and ylides is presented. Results indicate that they bear an ester group at alpha-position.

Research has been conducted on the generation of the organochromium(III) species. Iodonium salts reaction with anhydrous chromium dichloride is described.

Research has been conducted on the oxidation of nitroxyl radicals to N-oxo ammonium salts used for alcohols as oxidants. Prediction of the nitroxyl radicals redox potential is discussed.

Ionic liquids based on metals have been prepared by directly mixing AuCl3 and 1-ethyl-3-methylimidazolium chloride under an inert atmosphere. The objective was to extend the variety of possible room-temperature molten salts. Raman spectra suggest that the primary gold species is AuCl4- and while ab initio measurements forecast that ((AuCl3)2(mu-Cl)) should be stable, no experimental evidence for its formation in a room-temperature melt was observed.

Research was conducted to determine the one-component synthesis of pyrylium salts using electrophilic cyclization. The scope of a novel acid-induced cyclization of ortho-alkynylated aromatic carbonyl functionalities into the isobenzopyrylium salts was investigated. The efficient one- and/or two-pot preparations of the corresponding 3-arylisoquinolines, which can act as key intermediates in the synthesis of many isoquinolie alkaloids but have proven difficult to access through current methodology is described.

The pH-dependent inhibition of 22 metal salts was systematically examined for the yeast Saccharomyces cerevisiae. It was observed that the inhibition of growth by Cu, Co or Ni salts is substantially increased by histidine auxotrophy and by increasing the pH of the medium. Deletion of the high-affinity histidine permease Hip1p in His- strains caused greater sensitivity to Cu, Co and Ni and the requirement of a higher level of histidine to reverse the inhibition. It was concluded that intracellular histidine reduces the pH-dependent toxicity of Cu, Co and Ni.

Research was conducted to reexamine the salt effect to solve the problem of poor reproducibility. The synthesis of mesoporous silica molecular sieves was obtained in the presence of salts under different experimental conditions. A hydrothermal stability test in boiling water, X-ray diffraction, infrared spectroscopy and scanning electron microscopy were used to analyze the hydrothermal stability and structure of the silica materials. It was found that the time dependence was a very important factor for the improvement of the hydrothermal stability.

Variable magnetic and transport experiments show that the molecular charge transfer salt beta'-(bedt-ttf)4((H3O)Fe(C2O4)3)*C5H5N, where bedt-ttf = bis(ethylenedithio)tetrathiafulvalene, has a metal to superconductor transition at 8.6 K. However, the corresponding pyridine solvate is found to have a metal to insulator transition at 116 K. Based on the crystal structures of both complexes, the difference in transport properties is due to induced disorder in half of the bedt-ttf molecules in the pyridine solvate. This disorder is confirmed by structural studies at 90 K.