4.
New developments in the methodology available for the assessment of topical corticosteroid-induced skin blanching - Haigh, J.M.; Smith, E.W.; Maibach, H.I.
Since the publication of the previous edition of this book there have been considerable developments and controversy in the field of topical corticosteroid bioequivalence assessment. There has been considerable discussion in the literature concerning the use of the Minolta chromameter for the measurement of corticosteroid-induced skin blanching, as it is believed this instrument would produce more objective results than the visual grading procedure. These efforts culminated in the release of a guidance document from the Food and Drug Administration (FDA) detailing the procedures to be followed for the determination of topical corticosteroid bioequivalence using the chromameter. Since the promulgation of...
6.
The effects of elevated and ambient temperature conditions on dilutions of fluocinolone acetonide ointment assessed using the human skin-blanching assay - Haigh, J.M.; Smith, E.W.
Topical corticosteroid formulations have been in use now for some 30 years and many methods are available for the in vivo assessment of these preparations. Of all the assays described in the literature, the one first advocated by McKenzie and Stoughton, the so-called vasoconstrictor assay, is one of the most reliable if performed by experienced researchers using - the optimised methodology. Topical application of corticosteroids produces a whitening (blanching) of the skin, the intensity of which is directly proportional to the clinical efficacy of the formulation. Assessment of the degree of blanching produced is therefore of use in determining the...
7.
Bioequivalence testing of topical dermatological formulations, the gap between science and legislation - Schwarb, F.P.; Smith, E.W.; Haigh, J.M.; Surber, C.
Bioavailability concerns for topical dermatological products are complex and it is especially difficult to determine the bioequivalence of similar topical formulations. Since only small amounts of drug dispersed in an appropriate vehicle are applied to the skin, the amount of drug that actually reaches the systemic circulation is often too small to be easily quantified. Additionally, it can be argued that the relevance of any serum/plasma concentration-time curve of a topical agent is questionable, since the curve reflects the amount of drug after the active moiety has left the site of action. For some topical drugs e.g., topical corticosteroids, it...
8.
Precision of tristimulus chromameter results from corticosteroid-induced skin blanching - Smith, E.W.; Haigh, J.M.
The human skin blanching (vasoconstriction) assay has been in use for 3 decades as a tool for the assessment of the release of corticosteroids from topical dosage forms. Application of corticosteroids produces a whitening (blanching) of the skin, the intensity of which is directly related to the clinical efficacyof the formulation. Assessment of the intensity of the induced blanching has classically been, and continues to be, pe1fonned by visual grading, a method which has been criticised because of the subjectivenature of the assessment Recently there has been considerablediscussion in the literature regarding the use of the chromameter as an objective...
9.
The use of supersaturated solutions for the percutaneous delivery of rooperol tetra-acetate - Pefile, S.C.; Haigh, J.M.; Smith, E.W.
A major problem encountered in the transdennal delivery of drugs is the effectiveness of the barrier system imposedby the stratum corneum.To overcome tbe resistance of the skin to the ingress of exogenous chemicals, numerous innovative techniques requiring complex delivery systems have been studied. Many of these systems attempt to alter the barrier potential by the use of enhancer technology. Supersaturation, on the other hand, is a simple and economical technique which is not intended to modify the physical structure or the chemical compositionof the stratum corneum, yet may effectively deliver a markedly greater mass of drug to the skin than...
10.
Chromametry: measuring precision of diurnal and local variation of human forearm skin colour - Schwarb, F.P.; Smith, E.W.; Haigh, J.M.; Surber, C.
Chromameters are compact portable instruments used for the assessment of surface colour based on the tristimulus analysis of a reflected xenon light pulse, and have been used for the quantification of erythema in the study of irritant dermatitis, and corticosteroid-induced skin blanching in the vasoconstriction assay. The variability and the reproducibility of chromameter results were investigated since it is known that the location and application force of the measuring head on the skin and the orthostatic maneuver of the arms influence the colour measurement. Furthermore the diurnal variation and the homogeneity of forearm skin colour were investigated.
11.
Comparison of visual CR-200 and CR-300 chromameter data obtained from the corticosteroid-induced skin-blanching assay - Schwarb, F.P.; Smith, E.W.; Haigh, J.M.; Surber, C.
In a recent Guidance document the American FDA recommended the use of a chromameterrather thanthe human eye for the assessment of the pharmacodynamic blanching response produced after topical application of corticosteroids. The purpose of this study was to investigate the appropriateness of the human eye and two types of chromameter for the estimation of skin blanching.
12.
Can shed snakeskin be considered to be a model membrane for human stratum corneum? - Haigh, J.M.; Beyssac, E.; Aiache, J.M.
Recently there has been some interest in the use of shed snake skin as a "model" membrane for in vitro diffusion studies. Many different species of snake have been utilised as well as different skin sites (dorsal and ventral). The species is usually named and sometimes the skin site is indicated butsometimes neither species nor skin site is reported. Insome countries it is particularly difficult to obtain human skin for in vitro experimentation and it is therefore important to have alternate biological or synthetic membranes which mimic human skin membranes for diffusion experiments. In South Africa. shed snake skin is...
15.
Where have all the fathers gone? Media(ted) representations of fatherhood - Prinsloo, J.
[From the introduction]: "It is in the mundane world that media operate most significantly. They filter and frame everyday realities, through their singular and multiple representations, providing touchstones, references, for the conduct of everyday life, for the production and maintenance of common-sense (Silverstone 1999, p.6). While it is broadly accepted that the media do not reflect society, they do provide us with a repertoire of roles and images which we encounter and with which we engage."
As the opening quote suggests, the media play a vital role in the circulation and mediation of ideas, attitudes and actions and their significance...
16.
Learning (dis)advantage in matriculation language classrooms - Prinsloo, J.
During the first decade of democracy in South Africa formal education has been characterised by sweeping policy shifts and consequent curriculum revision. In many instances, curricular revisions are criticised for failing to effect desired or anticipated changes. In this chapter the focus is on the language curriculum and the associated practices, or what I refer to as the literacy practices that have become naturalised over decades and persist in the present. The argument that is presented here contends that to enable effective change, it is essential to understand better what has historically constituted literacy practices and to recognise their social,...
17.
Late Pleistocene and Early Holocene foragers in southern Africa - Lewis, C.A.
Foragers occupied parts of southern Africa, including the mountains of the Drakensberg, during the Birnam Interstadial (c. 35 000 c. 24 000 year BP). The Drakensberg was apparently unoccupied during the succeeding Bottelnek Stadial (c. 24 000 c. 15 000 year BP) but was re-occupied during the Late Glacial. Lowland areas near the coast were apparently occupied throughout the Late Pleistocene and Early Holocene.
18.
Ecological thinking: Schopenhauer, J.M. Coetzee and who we are in the world - Wright, L.S.
For the ecological agenda to make substantive progress, we will have to see powerful people and social agencies turning away from the ecological insanity that threatens us all, and for this to happen, people need to embrace voluntary renunciation, on the understanding that this is not self-sacrifice, but a different and more satisfying way of being in the world. The paper offers some thought, provoked by reading J.M. Coetzee and Arthur Schopenhauer, about what would make this change possible, what might enable it; and secondly why it is implausible that any such ideal might actually come to pass.
19.
A research prospectus for the humanities - Wright, L.S.
The humanities in South Africa, as elsewhere, face a crisis of credibility.There is pressing need for the humanities to articulate their social and educational purpose more clearly, so that their academic value is recognised beyond the confines of academia.The aim of reshaping human character and society remains the foundational impulse of the humanities. This is achieved through the careful study of specially selected exemplary 'texts': literary works, fine art, social schemes, intellectual movements, historical episodes, and philosophical and religious outlooks.Students are required to respond in person to both 'text' and the discourse of which it is an exemplary instantiation. This...
20.
Disgrace as J.M.Coetzee's Tempest - Wright, L.S.
Amid the deluge of criticism and commentary evoked by Disgrace, quite remarkably nobody has noticed that the book re-engages exactly the energies Shakespeare deployed in The Tempest, a play which has become an icon, if not the icon, of colonial and post-colonial studies.
1.
