In the title compound, [Pb(C(8)H(7)O(2))(2)(C(6)H(6)N(2)O)](n), the Pb(II) ion is coordinated by two 4-methyl-benzoate (PMB) and one nicotinamide (NA) ligands while symmetry-related NA ligands bridge adjacent Pb(II) ions, forming polymeric chains along the c axis. The carboxyl-ate groups in the two PMB ions are twisted away from the attached benzene ring by 22.9 (2) and 4.6 (2)°. The two benzen...

We report the first in situ detection of metal ions in the upper atmosphere of Mars resulting from the ablation of dust particles from comet Siding Spring. This detection was carried out by the Neutral Gas and Ion Mass Spectrometer on board the Mars Atmosphere and Volatile Evolution Mission. Metal ions of Na, Mg, Al, K, Ti, Cr, Mn, Fe, Co, Ni, Cu, and Zn, and possibly of Si, and Ca, were identi...

T HE CELL MEMBRANE of mammalian heart muscle cells may be characterized by three interrelated observations. In the first place, the membrane separates an intracellular solution having a high potassium (K) and a low sodium (Na) concentration from an ex-tracellular solution with a high Na and low K concentration. Secondly, K and Na ions can be shown with radioactive tracer technics to be continuo...

Channels and transporters of monovalent ions are increasingly suggested as putative anticarcinogenic targets. However, the mechanisms involved in modulation of proliferation by monovalent ions are poorly understood. Here, we investigated the role of K+, Na+, and Cl(-) ions for the proliferation of Ehrlich Lettre ascites (ELA) cells. We measured the intracellular concentration of each ion in G(0...

Tetrodotoxin-resistant (TTX-R) Na(+) channels are much less susceptible to external TTX but more susceptible to external Cd(2+) block than tetrodotoxin-sensitive (TTX-S) Na(+) channels. Both TTX and Cd(2+) seem to block the channel near the "DEKA" ring, which is probably part of a multi-ion single-file region adjacent to the external pore mouth and is involved in the selectivity filter of the c...

The influence of constitutive (Agl, lions) and nonconstitutive (Na+ ions) components of silver iodide hydrosols on the transformation rate of metaphasic silver iodide into crystalline silver iodide is studied. The simultaneous change of Agl, l ions, and Na+ ions concentrations causes a complex change of the value of the constant k, (which is proportional to the aggregation rate constant k 2). W...

The concept of an intimate linkage between active cationmovements across cell membranes and adenosine-triphosphatase activity is strongly supported by the parallelism between the effects of cations, notably Na+ and K+, and of cardiac glycosides, such as ouabain, on these two processes. The adenosine triphosphatases are activated by suitable concentrations of Na+ and K+ ions, this activation bei...

A total of 252 water samples were collected from 42 sites across the upper Han River basin during the time period from 2005-2006. Major ions (Cl(-), NO3(-), SO4(2-), HCO3(-), Na+, K+, Ca2+ and Mg2+), Si, water temperature, pH, EC and TDS were determined and consequently correlation matrix, analysis of variance, factor analysis and principal component analysis were performed in order to identify...

Nicotianamine (NA) is a non-protein amino acid derivative synthesized from S-adenosyl L-methionine able to bind several metal ions such as iron, copper, manganese, zinc, or nickel. In plants, NA appears to be involved in iron availability and is essential for the plant to complete its biological cycle. In graminaceous plants, NA is also the precursor in the biosynthesis of phytosiderophores. Ar...

Voltage-gated Na channels of cerebellar Purkinje neurons express an endogenous open-channel blocking protein. This blocker binds channels at positive potentials and unbinds at negative potentials, generating a resurgent Na current and permitting rapid firing. The macroscopic voltage dependence of resurgent current raises the question of whether the blocker directly senses membrane potential or ...