hillEquation: Estimation of the Half Maximal Inhibitory Concentration

In oro.pet: Rigorous - Positron Emission Tomography

Description

The half maximal inhibitory concentration (IC50) is a measure of the effectiveness of a compound in inhibiting biological or biochemical function. This quantitative measure indicates how much of a particular drug or other substance (inhibitor) is needed to inhibit a given biological process (or component of a process) by half.

Usage

hillEquation(conc, occ, guess = c(1, 100), control = minpack.lm::nls.lm.control())

Arguments

conc	a vector of drug concentrations in plasma (example units are ng/mL).
occ	a vector of PET occupancy values that correspond to the measured drug concentrations in plasma.
guess	a length-two vector of starting values for the nonlinear optimization.
control	is a list of parameters used by nls.lm.control that are set by default, but may be customized by the user.

Details

See reference(s).

In this version of the function the maximal occupancy (rmax) is estimated automatically. This should be optional.

Value

IC50	Half maximal inhibitory concentration
rmax	Estimated maximal occupancy
IC50SE	Approximate standard error for IC50
rmaxSE	Approximate standard erorr for rmax
hessian	Hessian matrix from the Levenburg-Marquardt procedure
info	Return value from the Levenburg-Marquardt procedure
deviance	Deviance from the Levenburg-Marquardt procedure
message	Text message from the Levenburg-Marquardt procedure

Author(s)

Brandon Whitcher [e-mail]

References

http://en.wikipedia.org/wiki/Hill_equation_(biochemistry) http://en.wikipedia.org/wiki/IC50

See Also

nls.lm

oro.pet documentation built on May 2, 2019, 6:53 p.m.