The pharmacokinetics and biotransformation of the antiretroviral agent nevirapine (NVP) after autoinduction were characterized in eight healthy male volunteers. Subjects received 200-mg NVP tablets once daily for 2 weeks, followed by 200 mg twice daily for 2 weeks. Then they received a single oral dose (solution) of 50 mg containing 100 microCi of [(14)C]NVP. Biological fluids were analyzed for...

Background: The most popular building materials are soil bricks and different types of stones. Radon is released into ambient air from soil and stones due to ubiquitous uranium and radium in them, thus increasing the airborne radon concentration. The radioactivity in soils is related to radioactivity in the rocks from which the soil is formed. In the present investigation, the radon em...

Sunitinib is an oral multitargeted tyrosine kinase inhibitor approved for the treatment of advanced renal cell carcinoma, imatinib-refractory gastrointestinal stromal tumor, and advanced pancreatic neuroendocrine tumors. The current studies were conducted to characterize the pharmacokinetics, distribution, and metabolism of sunitinib after intravenous and/or oral administrations of [(14)C]sunit...

Secure determination of the binding of 99mTc-radiopharmaceuticals to plasma (P) and blood cell (BC) constituents can help to understand the biodistribution of radiophamaceuticals. The reported precipitation studies of blood with radiopharmaceuticals have shown that the results can not be easily compared between studies. We decided to determine the "gold standard" concentration of trichloroaceti...

Sulfuryl fluoride (SO(2)F(2)) is a structural fumigant gas used to control drywood termites and wood-boring beetles. The pharmacokinetics and metabolism of inhaled SO(2)F(2) were evaluated in male Fischer-344 rats exposed to 30 or 300 ppm (35)S-labeled SO(2)F(2) for 4 h. Blood, urine and feces were collected during and after the exposures and analyzed for radioactivity, (35)S-labeled fluorosulf...

Abstract In this study, the effect of various types fertilizers on natural radioactivity levels in agricultural soil was investigated research. The activity concentration 226Ra, 232Th, and 40K fertilizer samples were determined by using gamma-ray spectroscopy a high-purity germanium (HPGe) detector to determine concentrations 40K. for phosphate raw (2300-5400) Bq/kg, (9-53) (56-3000) respective...

The aim of the present study was to investigate beta-adrenergic receptor and angiotensin II (Ang II) receptor modulation of norepinephrine release in human atria. Slices of human atrial appendages were incubated with [3H]norepinephrine, superfused with Krebs-Henseleit solution, and electrically stimulated in superfusion chambers. Pretreatment of the tissue with 6-hydroxydopamine (1.2 mmol/L) be...

The cells of a streptomycin-dependent strain of Bacillus megaterium took up only 2 to 5% of the dihydrostreptomycin present in the medium when grown in the minimum concentration of streptomycin required for growth. During growth in the presence of (3)H-dihydrostreptomycin, radioactivity was accumulated intracellularly in three forms, namely, unbound, loosely bound to the ribosomes (removable by...