Aluminon: its limited application as a reagent for the detection of aluminum species

The triammonium salt of aurin tricarboxylic acid, commonly referred to as aluminon, forms a dye that has been used for the colorimetric determination of Al(III) species. We have reviewed the pertinent literature on the reaction of aluminon with respect to the metallic species that form colored aluminon complexes. The effects of experimental variables, such as time, temperature, and pH, upon the color development of the aluminon complex are also presented. Organic and inorganic species, particularly Be(II) and Fe(III), which can affect color formation, are described. The use of aluminon as a histochemical staining agent for the detection of aluminum requires verification by atomic absorption spectrophotometric analysis or other quantitative techniques.     

Small angle neutron scattering studies of HbA in concentrated solutions.

Differential cross-sections for neutrons scattered by normal human hemoglobin have been determined over the range of concentrations from 2 to approximately 35 weight percent. Data are compared with structure factors calculated from models of monodisperse hard spheres interacting through a screened Coulomb potential. Good agreement is noted when the volume fraction eta is adjusted during multivariate fitting of data, but the fitted value of eta is always lower than expected from the known Hb concentration of the samples. Calculations of cross-sections for polydisperse scatterers suggest that the samples may contain oligomers of the fundamental tetrameric Hb molecule.     

Polypeptide neurotoxins modify gating and apparent single-channel conductance of veratridine-activated sodium channels in planar lipid bilayers

Summary The effects of scorpion and sea anemone polypeptide toxins on partially purified veratridine (VER)-activated Na channels from rat brain were studied at the single-channel level in planar lipid bilayers. The probability of the VER-activated channel being open (P _o ) increased with depolarization;P _o was 0.5 at –40 to –50 mV. Saxitoxin (STX) blocked VER-activated channels with an apparent dissociation constant of about 1nm at –45 mV. The apparent single-channel conductance was approximately 9 pS, similar to that seen in VER-activated Na channels from skeletal muscle transverse tubules. Addition of sea anemone or scorpion polypeptide toxins to VER-activated Na channels resulted in a 19% increase in apparent single-channel conductance and a hyperpolarizing shift in theP _o vs. V _m relation such that the channels were more likely to be open at potentials <40 mV. These effects of the polypeptide toxins on the single-channel properties of VER-activated Na channels may account for the previously described potentiation of VER action by polypeptide toxins.     

Effects of stressors on blood glucose and hepatic glycogen concentrations in turkey poults.

1. The putatively stressful procedures of sexing, toe trimming, snood removal, beak trimming and injection of antibiotic solution, as performed in a commercial hatchery, elevated blood glucose levels and depressed hepatic glycogen levels in newly-hatched turkey poults. 2. The first procedure performed, cloacal sexing, was sufficient to elevate blood glucose, but all procedures were required before depression of hepatic glycogen occurred. 3. Blood glucose levels declined in both untreated (INITIAL) and fully-treated (FINAL) poults over a 24 hr holding period. 4. Hepatic glycogen declined with 24 hr holding of INITIAL poults but increased with holding of FINAL poults.