Iron in iron overload disease is present as non-transferrin-bound iron, consisting of iron, citrate, and albumin. We investigated the redox properties of iron citrate by electrochemistry, by the kinetics of its reaction with ascorbate, by ESR, and by analyzing the products of reactions of ascorbate with iron citrate complexes in the presence of H2O2 with 4-hydroxybenzoic acid as a reporter molecule for hydroxylation. We report -0.03 V < E°' > +0.01 V for the (Fe(3+)-cit/Fe(2+)-cit) couple. The first step in the reaction of iron citrate with ascorbate is the rapid formation of mixed complexes of iron with citrate and ascorbate, followed by slow reduction to Fe(2+)-citrate with k = ca. 3 M(-1) s(-1). The ascorbyl radical is formed by iron citrate oxidation of Hasc(-) with k = ca. 0.02 M(-1) s(-1); the majority of the ascorbyl radical formed is sequestered by complexation with iron and remains EPR silent. The hydroxylation of 4-hydroxybenzoic acid driven by the Fenton reduction of iron citrate by ascorbate in the presence of H2O2 proceeds in three phases: the first phase, which is independent of the presence of O2, is revealed as a nonzero intercept that reflects the rapid reaction of accumulated Fe(2+) with H2O2; the intermediate oxygen-dependent phase fits a first-order accumulation of product with k = 5 M(-1) s(-1) under aerobic and k = 13 M(-1) s(-1) under anaerobic conditions; the slope of the final linear phase is ca. k = 5 × 10(-2) M(-1) s(-1) under both aerobic and anaerobic conditions. Product yields under aerobic conditions are greater than predicted from the initial concentration of iron, but they are less than predicted for continuous redox cycling in the presence of excess ascorbate. The ongoing formation of hydroxylated product supports slow redox cycling by iron citrate. Thus, when H2O2 is available, iron-citrate complexes may contribute to pathophysiological manifestations of iron overload diseases.

Black African women in rural South Africa have a very low incidence rate of breast cancer, 5-10 per 100,000. The rate, however, is rising in the considerably increasing urban population. During the period 1994 to 1999 in Durban, enquiries revealed an average of 57 urban patients admitted to hospital each year, from a population of about 600,000 African women, indicating an age-adjusted annual incidence rate of 15.1 per 100,000. This incidence rate is very low in comparison with those in developed populations, which range from 40 to 89 per 100,000. In the African patients studied, the mean age on admission was relatively young, 54.1 +/- 10.9 years, almost a decade earlier than patients of developed populations. Moreover, the disease was very far advanced; 21.1% were at Stage III and 63.1% at Stage IV. As to exposure to risk factors, African women in general are characterised by certain protective factors. These factors, which closely resemble those of importance in patients in developed populations are, late menarche, early age at birth of first child, high parity (with usually prolonged lactation), and being physically active. However, with ongoing changes in the lifestyle of urban African women, the protective factors are decreasing in their intensity. Changes in these respects have been associated with rises in the disease's incidence rate. Clearly, because of the late stage of the disease at the time of the patients' admission to hospital, and hence their poor survival rate, intensive efforts should be made to educate women to seek help at an early stage of their disease. For its avoidance, feasible protective or restraining measures are primarily to adopt a 'prudent' lifestyle, in respect of both dietary and non-dietary components. However, the chances of these measures being meaningfully adopted in African urban communities, unfortunately, are negligible. In consequence, further increases in incidence rate would seem inevitable.

This paper focuses on policy initiatives and strategies used to promote the use of information and communication technologies (ICTs) in higher education in South Africa. It explores a wider international outlook and current debates in South Africa to map out an emerging South African perspective concerning the integration of ICT in higher education. It also provides a brief survey of key policy developments on e-education in general to contextualize the use of ICTs. In doing so, the paper addresses the following questions: What general goals do policy makers in South Africa express in national policy documents for the integration of ICT in the education system? What is the role of government regarding the use of ICT in higher education? What policies and strategies for ICT do leaders of South African higher education institutions develop? How do South African national priorities and higher education institutional strategies match? Higher Education Policy (2007) 20, 73-95.

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Oesophageal cancer, a highly lethal tumour, occurs to a variable extent in Africans in sub-Saharan African countries. In many, its incidence remains low, as in the Ivory Coast, Mali and the Gambia. However, in other African countries, the incidence rate has risen considerably, especially in city populations, as in Durban, South Africa, in Kyadondo, Uganda, and in Harare, Zimbabwe, rising to levels far higher than those reported in white populations. As to risk factors, in some African settings, smoking is a factor, and in others, alcohol consumption. Nutritionally, one enquiry, made in Durban, indicated the use of less-refined cereal products, with higher consumptions of vegetables and fruit, to be protective. In developed populations, protective factors are considered to be those characteristic of a "prudent" lifestyle. However, known risk factors largely fail to explain the high variability in the disease's occurrence. In seeking to combat the disease, it is thought unlikely that most Africans, especially urban dwellers, are willing to alter their lifestyle appropriately, even with the understanding that the changes would confer other protective benefits. This suggests that further rises, especially in the contexts of high incidence rates, are inevitable.

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