Much controversy exists about whether or not NH(+)(4) is translocated in the xylem from roots to shoots. In this paper it is shown that such translocation can indeed take place, but that interference from other metabolites such as amino acids and amines may give rise to large uncertainties about the magnitude of xylem NH(+)(4) concentrations. Elimination of interference requires sample stabiliz...

A number of physical and functional properties of native human plasminogen, carrying glutamic acid as the NH, terminus, and of proteolytically modified plasminogen, having lysine in the corresponding position, are compared. In order to exclude other variables, the two preparations were made from the same fresh plasma pool. The integrity of the NH,-terminal portion of the native protein was assu...

The paper presents the results of synthesis, IR spectroscopic and agrochemical study products adduct formation (internal salts) urea with nitric orthophosphoric acids. It has been established that synthesized substances are hygroscopic, readily soluble in water. spectral data indicate that, depending on “acid : urea” ratio final CO, NH2, groups acid molecules involved various compositions: [H 2...

Development of effective, yet safe, antithrombotic agents has been challenging because such agents increase the propensity of patients to bleed. Recently, naturally occurring polyphosphates such as extracellular DNA, RNA, and inorganic polyphosphates have been shown to activate blood coagulation. In this report, we evaluate the anticoagulant and antithrombotic activity of nucleic acid-binding p...

The title compound, sodium ammonium sulfate-telluric acid (1/1), Na(0.39)(NH(4))(1.61)SO(4)·Te(OH)(6), is isostructural with other solid solutions in the series M(1-x)(NH(4))(x)SO(4)·Te(OH)(6), where ammonium is partially replaced with an alkali metal (M = K, Rb or Cs). The structure is composed of planes of Te(OH)(6) octa-hedra alternating with planes of SO(4) tetra-hedra. The Na(+)/NH(4) (+) ...

The 220 MHz spectrum of the cyclic nonapeptide Phe-Phe-Leu-Ile-Ile-Leu-Val-Pro-Pro (all L), designated cyclolinopeptide A, is analyzed by decoupling, exchange of peptide NH protons with deuterium, and measurement of the temperature dependence of the NH chemical shift. Measurement of the NH doublet spacings gives values of J(Nalpha), the vicinal coupling of alpha-CH and NH protons of specific am...

Two new cantilever-type polyoxometalates Na(5)(NH(4)){V(IV)[(Mo(2)O(6))CH(3)C(O)(PO(3))(2)](2)}.13H(2)O (1) and (NH(4))(4){V(IV)[(Mo(2)O(6))NH(3)CH(2)CH(2)CH(2)C(O)(PO(3))(2)](2)}.6H(2)O (2) have been synthesized and characterized by IR spectroscopy, UV-visible spectroscopy, elemental analysis, TG analysis, XPS, (31)P NMR and single-crystal X-ray diffraction. The structure analysis reveals that...

In the present study, medaka embryos were exposed to acidified freshwater (pH 5) to investigate the mechanism of acid secretion by mitochondrion-rich (MR) cells in embryonic skin. With double or triple in situ hybridization/immunocytochemistry, the Na(+)/H(+) exchanger 3 (NHE3) and H(+)-ATPase were localized in two distinct subtypes of MR cells. NHE3 was expressed in apical membranes of a major...

1. The effects of oral hydrochloric acid, ammonium chloride, sodium bicarbonate and ammonium bicarbonate on urea and ammonium excretion in rats on a constant diet were studied. 2. Hydrochloric acid acidosis significantly reduced urea excretion in the rat, with an equimolar increase in NH+4 excretion and no change in their sum. In ammonium chloride acidosis, most of the additional nitrogen intak...