The distribution and properties of cytoplasmic binding sites for the synthetic glucocorticoid dexamethasone and the natural glucocorticoid corticosterone in the brain and the pituitary were studied in detail. Cortisol-17 beta acid, a derivative which does not bind to the glucocorticoid receptor but is a competitor of corticosterone binding to plasma, was used to overcome plasma interference. In...

Two convergent, independent lines of evidence are used to identify the rat liver glucocorticoid receptor. First, the electrophilic affinity label [3H]dexamethasone 21-mesylate is used to label covalently the steroidspecific binding site of the receptor. (Dexamethasone is defined as 9a-fluoro-ll~,l7,2l-trihydroxy-16a-methylpregna-1,4-diene-3,2O-dione.) Second, antibodies to the rat liver recepto...

An amoniumvanadate plus sodium molybdate mixed modifier Graphite Furnace Atomic Absorption Spectrometric method has been developed for determination of traces of lead in drinking water. The concentration of lead in the sample is obtained by direct comparison to linear working graph prepared from aqueous standards in the modifier medium, The results indicate the better performance of the pro...

Aryl hydrocarbon hydroxylase (AHH, cytochrome P1-450) is highly inducible in several human cells and tissues exposed to specific halogenated and nonhalogenated aromatic chemicals of the "3-methylcholanthrene-type." In laboratory animals AHH induction is known to be regulated by binding of inducers to the Ah receptor, a soluble intracellular protein. However, the induction mechanism in the human...

This work reports the preparation of a Tc generator based on conversion of Mo produced by neutron irradiation, into insoluble magnesium Mo-molybdates compounds as matrix. The effect of magnesium salt types and concentration, Mg:Mo molar ratios, pH of molybdate solutions, eluate volume as well as the addition order of molybdate and magnesium solutions’ influences on the final Tc were evaluated. ...

We measured the uptake rate of molybdatc and related kinetic parameters for nine taxa of cyanobacteria and for the natural phytoplankton communities of six freshwater lakes containing planktonic Nz-fixing cyanobacteria. Molybdate uptake followed saturation kinetics and was competitively inhibited by both tungstate and sulfate. Tungstate inhibited molybdate uptake in a nearly mole-for-mole fashi...

The fates and the rates of metabolism of acetate, trimethylamine, methylamine, and methanol were examined to determine the significance of these compounds as in situ methane precursors in surface sediments of an intertidal zone in Maine. Concentrations of these potential methane precursors were generally <3 muM, with the exception of sediments containing fragments of the seaweed Ascophyllum nod...

A new triple molybdate, potassium sodium cobalt tris-(molybdate), K0.4Na3.6Co(MoO4)3, was synthesized using solid-state reactions. The Co(2+) and one Na(+) cation are located at the same general site, each with occupancy 0.5. Another site (site symmetry 2) is occupied by Na(+) and K(+) cations, with occupancies of 0.597 (7) and 0.402 (6), respectively. The other two Na(+) cations and one of the...