Talk:Hormesis

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Revision as of 10:51, 12 October 2008 by imported>Anthony.Sebastian (→‎Hoping this is a reasonable approach: responding to Howard Berkowitz)
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 Definition A quantitative and qualitative dose-response relationship in which the effect at low concentrations occurs in the opposite direction from that expected from the effect observed at higher concentrations. [d] [e]
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Starting article on "hormesis"

Encouraging collaboration.

Hoping this is a reasonable approach

One of the first thing that hormesis brings to mind is type-0 and type-1 pharmacokinetics, especially drug (or toxin) clearance. Obviously simplified, zero-order kinetics has a basic model that the excretion process has infinite capacity, while first-order kinetics has a saturation point. More precisely, zero-order kinetics asssume a constant absolute rate of clearance, while first-order clearance assumes a constant fraction of the total body concentraion over time.

Such effects are at the high-end range of dose-effect mechanisms.

At a low end -- thinking of infection rather than drugs -- in biohazard mitigation and biological warfare work, there is a well-established "minimum infective concentration" (often expressed as the 50th percentile). Tularemia, for example, can establish disease with only a few cells, where more dangerous agents require a considerably larger concenntration.

Howard C. Berkowitz 12:32, 1 October 2008 (CDT)

Interesting, Howard. Will give this some thought, and check 'hormesis' references to see if anyone touches on the subject.--Anthony.Sebastian 16:51, 12 October 2008 (UTC)

Michaelis-Menten work relevant here?

Is this an area that should be in this discussion? Howard C. Berkowitz 13:08, 1 October 2008 (CDT)

Howard, how would you approach this? Would Briggs-Haldane kinetics serve better? Hope you will elaborate. --Anthony.Sebastian 16:51, 12 October 2008 (UTC)