Toxicological consequences

The toxicological consequences of P. brevis red tides are mass mortality of fishes exposed to the red tide toxic shellfish which, if consumed, result in human neurotoxic shellfish poisoning and an irritating aerosol which results from contact with P. brevis cell particles entrapped in seaspray. In all cases, the threshhold levels for intoxication are in the picomolar to nanomolar concentration ranges, implying a specific locus or loci of action for brevetoxins (reviewed in 6). 

Thompson, D. C. Thompson, J. A. Sugumaran, M. Moldeus, P. Biological and toxicological consequences of quinone methide formation. Chem.-Biol. Interact. 1993, 86, 129-162. 

Pennie WD. Use of cDNA microarrays to probe and understand the toxicological consequences of altered gene expression. Toxicol Lett 2000 112-113 473-477. 

Upadhya SC, Chinta SJ, Pai HV, Boyd MR, Ravindranath V. 2002. Toxicological consequences of differential regulation of cytochrome p450 isoforms in rat brain regions by phe-nobarbital. Arch Biochem Biophys 399 56-65. 

It is critical to realize that pesticide tolerances themselves are not safety standards but rather enforcement tools for indicating whether pesticides have been applied according to directions. Violative residues result when residue levels exceed the tolerance due to the misapplication of a pesticide, or when residues at any level are found on a commodity for which a tolerance was not established (which could result from product misuse). While a few isolated cases of violative residues have resulted in human harm, the vast majority of violative residues are of little or no toxicological consequence. 

Krishnan, K. and J. Brodeur. 1991. Toxicological consequences of combined exposure to environmental pollutants. Arc/i. Complex Environ. Stud. 3 1-106. 

It is tempting, given the above, to conclude that any degree of covalent binding of drug species to macromolecules will lead to a toxic response. However, this is clearly not the case as there are plenty of examples where covalent binding has had no toxicological consequence. 

According to the free drug hypothesis only the unbound drug is available to act at physiological sites of action, whether it is the intended pharmacological target, or action at an undesired site with potential toxicological consequences and a schematic... 

Try making a list of ail the different foods you have eaten in the past 24 hours and think of the challenges that you have given your biochemistry. Hundreds of NPs must have entered your system, most of which will be chemically unknown and of unknown toxicological consequence. Clearly, human experience has eliminated from the diet those foods that overburden the human body with harmful NPs. However, it is worth knowing that some plants (e.g., garlic) contains some very toxic NPs, chemicals that were they made synthetically, would not be allowed to be added to food. 

The acetylation polymorphism has a number of toxicological consequences, which will be discussed more fully in chapters 5 and 7. 

However, apart from absolute specificity, foreign compounds may also be substrates for enzymes involved in endogenous pathways, often with toxicological consequences. Thus, for example, with VPA (see above), fluoroacetate, and galactosamine (see chap. 7) involvement in endogenous metabolic pathways is a crucial aspect of... 

Saturation of the processes involved in the elimination of a foreign compound from the plasma, such as metabolism and excretion, may also have toxicological consequences. Thus, ethanol exhibits zero-order elimination kinetics at readily attainable plasma concentrations, because the metabolism is readily saturated. Therefore, once these plasma concentrations have been attained, the rate of elimination from the plasma is constant. Increasing the dosage of ethanol leads to accumulation and the well-known toxic effects. 

Toxicological consequences of induction will depend on whether metabolism is a detoxication process or not, but both the rate and route of metabolism of the compound may be... 

Hahidi H, Guzey G, Idle JR. Pharmacogenetics and toxicological consequences of human drug oxidation and reduction. In Ballantyne B, Marrs TC, Syversen T, eds. General and Applied Toxicology, Vol. 1. London Macmillan, 2000. 

Fuhr U. Induction of drag metabolising enzymes pharmacokinetic and toxicological consequences in humans. Clin Pharmacokinet. 2000 38 493-504. 

F Matsumura University of California Davis Determine the toxicological consequences of elevated protein tyrosine kinase activities in guinea pigs and mice and why 2,3,7,8-TCDD causes such an effect on EGF receptors... 

This metabolite like the 7-oxo product mentioned above may also have toxicological consequences. Although chemically quite stable, it may react in vivo with cellular components such as DNA which could lead to profound alterations in cellular processes. 

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