Background: Knowledge of radioactivity levels in human diet is of particular concern for the estimation of possible radiological hazards to human health. However, very few surveys of radioactivity in food have been conducted in Iran therefore the baseline values of the natural radionuclides concentration (40K, 226Ra and 232Th), and man made radionuclide, 137Cs, were determined in twenty six...

Plasma membrane vesicles were isolated from a subline of L929 mouse fibroblasts grown on defined medium in the absence of serum. These vesicles were not significantly contaminated by mitochondria or endoplasmic reticulum. The isolation procedure, a modification of that originally developed by McKeel and Jarett (McKeel, D.W., and Jarett, L. (1970) J. Cell Biol. 44, 417-432) employs mechanical ho...

BACKGROUND Advances in gamma camera technology and the emergence of a number of new theranostic radiopharmaceutical pairings have re-awakened interest in in vivo quantification with single-photon-emitting radionuclides. We have implemented and validated methodology to provide quantitative imaging of (177)Lu for 2D whole-body planar studies and for 3D tomographic imaging with single-photon emiss...

To predict the magnitude of P-glycoprotein (P-gp)-based drug interactions at the human blood-brain barrier (BBB), rodent studies are routinely conducted where P-gp is chemically inhibited. For such studies to be predictive of interactions at the human BBB, the plasma concentration of the P-gp inhibitor must be comparable with that observed in the clinic. Therefore, we determined the in vivo EC(...

BACKGROUND The economic value of unconventional natural gas resources has stimulated rapid globalization of horizontal drilling and hydraulic fracturing. However, natural radioactivity found in the large volumes of "produced fluids" generated by these technologies is emerging as an international environmental health concern. Current assessments of the radioactivity concentration in liquid waste...

The archaeal plasma membrane consists mainly of diether lipids and tetraether lipids instead of the usual ester lipids found in other organisms. Although a molecule of tetraether lipid is thought to be synthesized from two molecules of diether lipids, there is no direct information about the biosynthetic pathway(s) or intermediates of tetraether lipid biosynthesis. In this study, we examined th...

1. An increase in polyamine concentration, caused by inhibiting the amine oxidase activities with iproniazid, increased the incorporation of [3H]orotic acid into chick-embryo RNA and DNA. On the other hand, a decrease in polyamine concentration, obtained by causing an increase in amine oxidase activities, decreased [3H]orotic acid incorporation into nucleic acids. This was particularly evident ...

Absorption, metabolism, and excretion of [14C]viramidine, a prodrug of ribavirin, were studied in humans following a single oral dose (600 mg). Viramidine was rapidly absorbed, with a time to maximum concentration of the drug in plasma of 1.5 h. Viramidine and ribavirin accounted for only 4.3% and 42% of plasma area under the concentration-time curve (AUC) for radioactivity, respectively, indic...

Background: Salivary flow rate (SFR), to estimate salivary gland dysfunction and radioactivity in different body fluids, to evaluate its intensity, were determined in thyroid patients after 131-I therapy. Material and Methods: For determination of SFR an innovative sponge test was adopted and the radioactivity in saliva, blood and serum of thyroid patients was determined by NaI (TI) Scintillati...