Biomedical subjects
A Roddick
Publications and source records attributed to A Roddick.
Leadership in dental public health? Wanted: a catcher in the rye.
Changes in the structure of the health services have resulted in a vacuum in leadership in dental public health. The competitive model, introduced in 1993, had several serious effects on the delivery of publicly-funded dental health services. Some Crown Health Enterprises greatly reduced their expenditure by employing fewer public health dentists. This resulted in major disparities in the supervision of school dental services, and in a reduction in health-services research. Problems in publicly-funded dental health services are accumulating, but no leadership to meet these problems seems to be emerging. Because of this failure, it may now be up to the providers to assume the leadership role.
Determination of rate and equilibrium constants for the reactions between electron transfer mediators and proteins by linear sweep voltammetry.
Redox proteins undergo measurable charge transfer at electrodes only under special circumstances, while they readily take part in electron transfer reactions with mediators in solution. Advantage was taken of the latter fact to develop a new method to study the kinetics and equilibria of protein-mediator electron transfer reactions. It was shown that rate and equilibrium constants for the electron exchange between electron transfer mediator and the protein can be obtained from the analysis of the perturbation of the linear sweep voltammetry (LSV) response of the mediator due to the presence of the protein. The experiments were carried out under conditions where the protein does not interact with the electrode. Theoretical data obtained by digital simulation are presented to show the conditions under which rate and equilibrium constants are accessible by the LSV technique. The electron transfer reactions between ferri- and ferrocytochrome c and N,N,N',N'-tetramethylphenylenediamine and the corresponding radical cation in phosphate-buffered saline (0.04 M phosphate, pH 7.4, 0.1 M NaCl) buffer were selected to demonstrate the technique. These studies resulted in an equilibrium constant equal to 1.0 and forward and reverse rate constants equal to 1.6 x 10(4) M-1 s-1. The data available from this method include forward and reverse rate constants for electron transfer and the formal potential for the protein redox couple.