Both behavior and morphology can be altered by exposure of the CNS to toxic substances. The brain is an organ with considerable structural redundancy and this presumably accounts for some of the ability of the CNS to maintain normal function in the presence of some structural damage. Compensation for damage may also occur through a form of "learning" due to the biochemical and morphological pla...

Bistability is considered wide-spread among bacteria and eukaryotic cells, useful, e.g., for enzyme induction, bet hedging, and epigenetic switching. However, this phenomenon has mostly been described with deterministic dynamic or well-mixed stochastic models. Here, we map known biological bistable systems onto the well-characterized biochemical Schlögl model, using analytical calculations and ...

Information on how drugs are metabolized is not only of importance in understanding their therapeutic action, but can furnish useful clues for the development of new drugs. The various aspects of drug metabolism studies which are considered in this paper are (i) Pathways of drug metabolism— conversion to active, inactive or toxic metabolites; (ii) Structural changes which determine a drug's met...

objective: this study was conducted with the aim to investigate and compare iranian produced and foreign oxytocin for use in induction of labor. materials and methods: this random clinical trial was conducted on a population of 198 pregnant women with live fetus and cephalic presentation and conditions conducive to induction of labor, monitored by obstetricians and gynecologists. they were rand...

A study of the formation of induced (adaptive) enzymes in purine or pyrimidine requiring mutants of Escherichia coli was reported in a previous publication (Pardee, 1954). The idea that synthesis of ribonucleic acid (RNA) is essential for protein synthesis is supported by the inability of the bacterial mutants to form protein and several enzymes, including f3galactosidase, in the absence of pur...

Toxic responses to test chemicals are known to be dependent on the exposure route, the kinetic behavior of the chemical, and the dose used in the toxicology study. Therefore, knowledge of internal dose is indispensable for the interpretation of toxicology study results, for the facilitation of interspecies scaling, and for risk assessment. By monitoring the blood and/or tissue concentrations of...

When a 40 min pulse of leucine-3H was administered to rats 2 hrs after 75 mg/kg of phenobarbital (Pb), there was a 70% increase above control in labeling of microsomal protein and of a nuclear protein fraction extracted with 1 M NaCl. When a 40 min pulse of labeled leucine was given 24 hrs after a single injection of Pb (75 mgfkg), there was a 42% stimulation in the specific activity of microso...

-Naphthoflavone (BNF) is a synthetic flavone that selectively and potently induces CYP1A enzymes via aryl hydrocarbon receptor activation. Mechanism-based mathematical models of CYP1A enzyme induction were developed to predict the time course of enzyme induction and quantitatively evaluate the interrelationship between BNF plasma concentrations, hepatic CYP1A1 and CYP1A2 mRNA levels, and CYP1A ...

β-Naphthoflavone (BNF) is a synthetic flavone that selectively and potently induces CYP1A enzymes via aryl hydrocarbon receptor activation. Mechanism-based mathematical models of CYP1A enzyme induction were developed to predict the time course of enzyme induction and quantitatively evaluate the interrelationship between BNF plasma concentrations, hepatic CYP1A1 and CYP1A2 mRNA levels, and CYP1A...