Biomedical subjects

Paul S Agutter

Publications and source records attributed to Paul S Agutter.

3 recordsLinked to original sources

PubMed2004

Metabolic scaling: consensus or controversy?

BACKGROUND: The relationship between body mass (M) and standard metabolic rate (B) among living organisms remains controversial, though it is widely accepted that in many cases B is approximately proportional to the three-quarters power of M. RESULTS: The biological significance of the straight-line plots obtained over wide ranges of species when B is plotted against log M remains a matter of debate. In this article we review the values ascribed to the gradients of such graphs (typically 0.75, according to the majority view), and we assess various attempts to explain the allometric power-law phenomenon, placing emphasis on the most recent publications. CONCLUSION: Although many of the models that have been advanced have significant attractions, none can be accepted without serious reservations, and the possibility that no one model can fit all cases has to be more seriously entertained.

Animals↗

PubMed2003

Directions in biomedical research: a plea for ideological pluralism.

Feinstein [A.R. Feinstein, Am. J. Med. 107 (1999) 461] complained that 'basic medical science' has overwhelmed 'pathophysiological medical science' during the past half century, and 'destroyed the bridge between bedside and bench'. We agree that a 'drastic reorientation' will be necessary to correct the overemphasis and imbalance. Re-examining the roots of his problem, we believe that a plea to restore a balance between the 'status' (esteem) of 'large research' and 'small research' in medical science brings back into question the decision of academic physiologists to invoke the framework of Physics in/of 1847 [P.F. Cranefield, J. Hist. Med. Allied Sci. 12 (1957) 407] (together with an absolutist 'Prime Mover'/Metaphysic which Einstein would delete from Physics in 1905). The current 'imbalance' arose when that Cartesian 'Prime Mover' was NOT deleted from the Biological frame. Feinstein felt that the 'privileged status' (esteem) in which fund-giving bodies hold 'Small' researches compared to 'Large' should be cancelled. Once Biology replaces its Cartesian absolutism with a relativist framework, redress will follow naturally when living-material has regained the status of cause as well as effect. Descartes' 'Great Watchmaker' is a Dead God in Biology: a non-metaphysical Biological Perspective would restore balance between 'large' and 'small' investigations. ('Pluralism' implies that no scientific perspective would be second-rate in a relativist framework.)

Animals↗

PubMed2003

Stochastic description of the ligand-receptor interaction of biologically active substances at extremely low doses.

Signalling molecules can be effective at extraordinarily low concentrations (down to attomolar levels). To handle such cases, probabilistic methods have been used to describe the formal kinetics of action of biologically active substances in these low doses, although it has been necessary to review what is meant by such a term. The mean numbers of transformed/degraded molecules and their dispersions were calculated for the possible range of ligand-receptor binding schemes. We used both analytical equations and numerical simulations to calculate the coefficients of variation (ratio of standard deviation to mean) and demonstrated that the distribution of the coefficient is highly dependent on the reaction scheme. It may, therefore, be used as an additional factor for discriminating between cooperative and noncooperative models of ligand-receptor interaction over extreme ranges of ligand dilution. The relevance to signalling behaviour is discussed.

Animals↗